Which of the following is an example of unearned income?

Unearned income refers to money earned from sources that do not involve active work or efforts in the traditional sense, often categorized as passive income. Interest from a savings account is classified as unearned income because it is generated passively when money is deposited in a bank or financial institution. The individual does not actively 'work' to earn this money; instead, they earn interest simply by having funds in the account.

In contrast, the other options denote forms of earned income, which result from the individual's active involvement in work or services provided. Monthly salary, bonuses from work performance, and commission from sales all stem from actively engaging in employment, selling products, or delivering services. Thus, these sources require participation and effort, distinguishing them as earned income rather than unearned.