The correct option is C Commission
Errors of commission are the errors that are committed due to wrong posting of transactions, wrong totaling or balancing of the accounts, the wrong casting of the subsidiary books, or wrong recording of the amount in the books of original entry, etc. For example Rs. 4,000 received from Shyam credited to Shyam Associates A/c. This constitutes an error of commission. Such an error by definition is of clerical nature and most of the errors of commission effect in the trial balance.