BB Limited is a subsidiary of AA Limited. When AA acquired its 80% interest in BB, the retained earnings of BB were $10000. At the beginning of the current period BB Limited's retained earnings were $40000. BB earned profit after tax of $20000 during the current period. The total share of the non-controlling interest in the equity of BB Limited at the end of the current period is:

Select one:

a.$15 000

b.$17 500

c.$12 000

d.$7 500

e.$16 000