Atrial balance may prove that debits and credits are equal, but . an amount could be entered in the wrong account. b. a transaction could have been entered twice. c. a transaction could have been omitted. d. all of these answer choices are correct.

d. All of these answer choices are correct.

Explanation:

Considering all the options;

a. an amount could be entered in the wrong account. - This is true as a transaction that should have been recorded into the asset account could be erroneously recorded as an expense or vice versa. The same applies to expenses and liabilities

b. a transaction could have been entered twice. - This is true. If a transaction is entered twice correctly, the debits would equal the credits

c. a transaction could have been omitted. -  this is true. The omission will not result in unequal debits and credits.

Hence the answer is d. All of these answer choices are correct.