Suppose Jack starts 1st period with 0 wealth but earns 200, his second period income is 700 and his last and 3rd period income is 300. He does not care about a 4th period. The real interest rate is 0 but he cannot borrow. He wants to smooth consumption perfectly across the 3 periods. His consumption and saving in the 1st period are

A.400 and 200, respectively.

B.400 and -200, respectively.

C.200 and 200, respectively.

D.200 and 0, respectively.