【单选题】

In a certain conservative mutual fund, 70 percent of the money is invested in bonds, and of that portion, 40 percent is invested in highly rated corporate bonds. If at least $1.4 million in this fund is invested in highly rated corporate bonds, what is the smallest possible total value for the mutual fund

A、$4 million
B、$5 million
C、$6 million
D、$7 million
E、$8 million