The correct answer is: A. simple revision.
Adding a new account to the chart of accounts at the beginning of an accounting period is a simple revision because it does not require any changes to the existing accounts or the financial statements. The new account can simply be added to the chart of accounts and used to track the new type of transaction.
A moderately complex revision would be adding a new account to the chart of accounts in the middle of an accounting period. This would require changing the existing accounts to reflect the new type of transaction, as well as adjusting the financial statements for the transactions that have already occurred.
A complex revision would be changing the structure of the chart of accounts. This would require changing the existing accounts and the financial statements.
E is not an option because it is not a valid answer.