Option a): This definition pertains to a more limited view, focusing primarily on net income and specific adjustments, not encompassing all components of comprehensive income.

Option b): Correct. Comprehensive income includes all changes in equity during a period from transactions and other events and circumstances from non-owner sources. This encompasses net income and other comprehensive income items such as unrealized gains or losses on investments, foreign currency translation adjustments, and revaluation surpluses.

Option c): This defines net income, which is a component of comprehensive income but does not capture the full scope, including other comprehensive income items.

Option d): This definition is incomplete and does not capture the broad spectrum of items included in comprehensive income, such as adjustments that are not related to owner transactions.

Option A (Unrealized gains or losses on available-for-sale securities): This is typically included in other comprehensive income because it represents changes in the fair value of financial assets that are not realized until the assets are sold.

Option B (Foreign currency translation adjustments): This is included in other comprehensive income as it reflects the adjustments needed when translating the financial statements of foreign subsidiaries into the reporting currency of the parent company.

Option C (Revaluation surplus on property, plant, and equipment): Under certain accounting standards (such as IFRS), this is included in other comprehensive income as it reflects changes in the value of long-term assets that are not immediately realized through sale.

Option D (Operating income from the company's core business operations): Correct. This is part of the regular income statement and reflects the profit generated from the company’s main activities. It is not included in other comprehensive income but rather in the net income section of the Statement of Comprehensive Income.

Option C is incorrect because, during the consolidation process, the income or loss of the acquired company is only included for the period after the acquisition. The revenues and expenses prior to the acquisition are not included in the consolidated financial statements.

Option A is correct because eliminating intercompany receivables and payables is necessary to avoid double counting the same transaction on both sides of the balance sheet.

Option B is correct because eliminating the parent’s investment account is part of the process to reflect the subsidiary's assets and liabilities as part of the consolidated entity without double counting the investment.

Option D is correct because eliminating the effect of intercompany sales of fixed assets ensures that any gains or losses from these transactions are not overstated in the consolidated financial statements.

Cash and cash equivalents are defined as short-term, highly liquid investments that are readily convertible to known amounts of cash and are subject to an insignificant risk of changes in value. Typically, these are investments with original maturities of three months or less. 

While bank deposits, short-term government bonds, and treasury bills with maturities of three months or less fit this definition, highly liquid investments with an original maturity of six months do not qualify as cash and cash equivalents due to their longer maturity period. Therefore, option C would not be classified as cash and cash equivalents.

Option a): This statement is correct in highlighting a limitation, but it doesn't specifically address historical cost accounting, which is the primary focus of the question.

Option b): This is incorrect because the question specifies historical cost accounting as the basis, not fair value accounting.

Option c): This is incorrect because financial statements only include transactions of the entity being reported on, not transactions of competitors.

Option d): Correct. Financial statements prepared using historical cost accounting reflect assets and liabilities at their original purchase cost, which may not reflect their current market value. This limitation can misrepresent the true economic position of the entity.

Management within a company relies on financial information to assess the efficiency of operations and the profitability of various business segments. This assessment is crucial for making informed decisions regarding the direction of the company, including whether to continue with current operations, expand into new areas, or diversify the business portfolio to mitigate risks and capitalize on new opportunities. 

Unlike shareholders who focus on returns, or creditors who focus on credit risk, management’s role is centered on strategic planning and operational effectiveness to drive long-term growth and stability. Regulatory authorities, on the other hand, are concerned with ensuring compliance and protecting the public interest rather than the company’s operational strategies.

• Internal Management (A): Focuses on using the financial data for internal decision-making and performance optimization.
• External Auditors (B): Concerned with the accuracy and fairness of the financial statements, but not directly involved in making investment or credit decisions.
• Regulatory Authorities (D): Interested in compliance and adherence to regulations, ensuring that the company operates within the legal framework.

Option a): This is incorrect because the statement of changes in stockholders' equity details changes in both individual equity accounts and total equity. The specificity in individual account changes is essential for a complete understanding of the equity variations.

Option b): Correct. The statement is typically presented in a columnar format where each column represents a different equity account, such as common stock, retained earnings, and additional paid-in capital, as well as a column for total stockholders' equity. This format ensures clarity in tracking changes over time.

Option c): This is incorrect because the statement of changes in stockholders' equity must be prepared for every year that comparative financial statements are presented, not just the most recent year. It provides continuity and context for understanding changes in equity.

Option d): This is incorrect because the statement must show detailed changes for each equity account regardless of the significance of the change in total stockholders' equity. Comprehensive disclosure is necessary to inform stakeholders about the sources and impacts of changes in equity.