Due to economic slowdown in 2009, a worker lost his job, which provided him VND 50 million. He gets a job-loss allowance of VND 30 million. His wife starts working for HSBC with a salary of VND 17 million, and their son increases the amount of support to his parents from VND 5 million to VND 18 million. The contribution of this worker’s family to GDP is: a. increase by VND 67 million b. decrease by VND 33 million c. increase by 13 millions d. unchanged