Benjamin retired at age 62 and began to collect Social Security retirement benefits. After a year of playing 3 rounds of golf per day, Ben is bored and decides to go back to work part-time. In 2016 (when Benjamin is age 63) he earns $25,720 at his part time job. His social security benefit before any adjustment for 2016 is $18,000. What will his actual Social Security benefit be for 2016? (a) $10,000. (b) $13,000. (c) $14,667. (d) $18,000.