Is it okay to state that under accrual basis of accounting… (schweser notes book 2 page 196 question 1 option (b)) Revenues and expenses may be allocated to time periods other than those in which the cash flows occur?
Absolutely!
Unearned income and depreciation are prime examples of each.
You can also understand it in another way that:
Under the accrual basis of accounting, revenues are reported on the income statement when they are earned.
Under the cash basis of accounting, revenues are reported on the income statement when the cash is received.
Under the accrual basis of accounting, expenses are matched with the related revenues and/or are reported
when the expense occurs, not when the cash is paid.
Ohh my bad … logical fallacy … i took the statement to be a negation of the fact that it can be reported in the period when the cash flow has occured. i thought the statement is suggestive to 'Revenues and expenses may be allocated to time periods other than(but not to!!! 
) those in which the cash flows occur? … Thnxx fot the replies though.