Choose the most appropriate option to change the voice (active / passive) form of the given sentence.
An apple carries about 100 million useful bacteria.

A

About 100 million useful bacteria are being carried by an apple.

B

An apple will carry about 100 million useful bacteria.

C

The useful bacteria to be carried in an apple is about 100 million.

D

About 100 million useful bacteria are carried by an apple.