Answer: the correct option is D.
Explanation: First we shall define Liabilities and Equity.
Liabilities are the obligations of a company, meaning that, they are amounts owed to creditors for past transactions and they usually have the word "payable" in their account title.
Equity is the remaining value of an owner's interest in a company, after all liabilities have been deducted.
From the definitions above, we can see that the liabilities of Mitchell Company have increased because the company owes the supplier. While the equity has decreased because it is what is left of the value of the company after the liabilities have been deducted.