Final answer:
The fund that focuses on the measurement of economic resources using accrual accounting is the private-purpose trust fund. This method recognizes revenues and expenses when they are earned and incurred, not just when cash is exchanged.
Step-by-step explanation:
The question asks about which fund focuses on the measurement of economic resources using accrual accounting. Among the options given, a) agency, b) private-purpose trust, and c) pension trust, the main answer is b) private-purpose trust. Private-purpose trust funds use accrual accounting to measure economic resources, which includes recognizing revenues when they are earned and expenses when they are incurred, regardless of when the cash transactions occur. Accrual accounting gives a more accurate picture of a fund's financial position.In contrast, agency funds typically use custodial activities which do not involve the measurement of results of operations. Pension trust funds do calculate accumulated resources for pensions but are generally more focused on the needs of public employee retirement systems and can use different accounting bases including accrual.Therefore, the correct answer is b) private-purpose trust funds, as they are the most aligned with the principles of accrual accounting.