Which of the Following Entries Could Not Be a Closing $\quad$

Which of the following entries could not be a closing entry?

A) Service Fees Earned
$\quad$ $\quad$ $\quad$ Income Summary
B) Income Summary
$\quad$ $\quad$ Salary Expense
C) Retained Earnings
$\quad$ $\quad$ $\quad$ Dividends
D) Dividends
$\quad$ $\quad$ $\quad$ Cash