The correct answer is option 'C': A personal account.

Explanation:
A personal account is an account that represents individuals, firms, or organizations with whom a business has a financial relationship. The premium on redemption of debentures account falls under the category of personal accounts because it represents a specific individual or organization.

The premium on redemption of debentures account is created when a company issues debentures at a premium, which means the debentures are issued at a price higher than their face value. The premium is the excess amount received by the company, and it is recorded in the premium on redemption of debentures account.

A personal account is a real account that records the transactions related to a specific person or entity. It is not a nominal account, which records income and expenses, or a real account, which records assets, liabilities, and capital.

The premium on redemption of debentures account is a liability for the company because it represents the amount that the company owes to the debenture holders. When the debentures are redeemed or repaid, the premium on redemption of debentures account is debited, and the debenture holders' account is credited.

In accounting, the classification of accounts into real, personal, and nominal categories helps in organizing and summarizing financial transactions. Personal accounts represent individuals or organizations, real accounts represent assets, liabilities, and capital, and nominal accounts represent income and expenses.

In summary, the premium on redemption of debentures account is a personal account because it represents a specific individual or organization.