On January 1, 2013, Petersen Corp

On January 1, 2013, Petersen Corp.sold a piece of equipment for $3,000 which it had used for several years.The equipment had cost $13,000, and its accumulated depreciation amounted to $9,000 at the time of the sale.What are the net effects on the accounting equation of selling the equipment?

A) Assets and Stockholders' Equity increase $1,000.
B) Assets decrease and Stockholders' Equity increases $3,000.
C) Assets and Stockholders' Equity decrease $1,000.
D) Assets and Stockholders' Equity decrease $3,000.