Final answer:
The parts of an income statement heading include the name of the entity (who), the title of the report (what), and the period covered by the statement (when), corresponding to option A. Therefore, the correct option is A.
Step-by-step explanation:
The three parts of an income statement heading are who, what, and when. This corresponds to option A: who, what, when. The 'who' refers to the name of the entity or company, the 'what' refers to the title of the report, in this case, 'Income Statement,' and the 'when' stands for the period that the statement covers, such as 'For the Year Ended December 31, 2022.'