Answer: a. the purchase of a personal automobile by the owner using personal funds.
Step-by-step explanation:
If the owner of a business purchases a car with their own funds, this does not impart equity or indeed any other portion of the business as this is a personal transaction that does not involve the business.
Purchasing a car for the owner's son with cash generated for the business will affect Equity by reducing it. Investment by owners will increase equity and a sale of goods will increase revenue which will affect equity via the net income.