Which of the following is an example of revolving credit?

Revolving credit is a type of credit that allows borrowers to access a specific amount of funds repeatedly, as long as they make the necessary repayments. A department store credit card is a prime example of revolving credit because it provides a credit limit that shoppers can use to make purchases, repay the amounts over time, and then borrow against it again, creating a cycle of usage and repayment.

This is in contrast to other forms of credit listed in the options. A home equity loan, for instance, is typically a one-time lump-sum loan with fixed repayment terms and does not offer the ability to borrow again without applying for a new loan. Similarly, a car loan is an installment loan, where the borrower receives funds in a single payment and makes fixed monthly payments until the loan is paid off. A payday loan is also structured as a single, short-term loan that must be repaid on the borrower's next payday, with no ongoing access to credit.

Therefore, the correct choice is the department store credit card, as it exemplifies the essential characteristics of revolving credit, allowing continuous borrowing within a set limit as repayments are made.