The Accounting Equation for Ying Company Shows a Decrease in Its

The accounting equation for Ying Company shows a decrease in its assets and a decrease in its equity. Which of the following transactions could have caused that effect?

A) Cash was received from providing services to a customer.
B) A utility bill was received for the current month, to be paid in the following month.
C) The company paid an amount due on credit.
D) Equipment was purchased for cash.
E) Advertising expense for the month was paid in cash.