Answer:
Reason : To ensure constant flow of cash
Step-by-step explanation:
Accrual Basis of accounting records transactions when they meet definition and recognition criteria of Assets, Liabilities,Equity, Expense and Incomes.
This is different from cash-basis accounting which records transactions at the receipt or payment of cash.
Because of timing difference, the cash transactions (cash basis) can happen a late than the day of recognition of the elements (accrual basis).
Hence Revenue services demand that income tax be calculated on accrual basis to ensure a constant flow of cash whenever an entity transact.