i have question so if i can get right answer

under the accrual basis of accounting adjusting entries are required to?

1. obtain a proper matching of revenue and expenses.
2. adjust accounting to reflect market values.
3. recongnize cash collected and disbursed.
4. all of the above.

Under accrual accounting revenue should be recognized when?

1. earned and an exchange has taken place.
2. an exchange has taken place.
3. cash is collected.
4. production is complete.