Answer:
A. Stockholders' equity decreases.
Explanation:
The accounting equation is defined as:
Assets = Liabilities + Stockholder's Equity
Stockholder's Equity = Common stock + Retained earnings
All the revenues and expenses are clubbed in retained earnings and ultimately in stockholder's equity.
Thus, any kind of expenses paid will reduce the revenues and then the retained earnings and further the stockholder's equity in accounting equation.
Therefore, correct option is:
A. Stockholder's Equity.