John is the owner of ABS Inc, an S corporation. At the beginning of the tax year, John's adjusted basis in ABS Inc. was $20,000. During the year, the corporation borrowed $25,000 from a bank for equipment purchases, but John was not required to guarantee the loan. ABS has net business income of $10,000 for the tax year. What is John's adjusted basis in ABS Inc. at the end of the tax year?

a) $ 5,000 b) $42,500 c) $30,000 d) $55,000