Select the correct passive form of the given sentence.A child could understand his theory. (a) His theory is being understood by a child. (b) His theory was understood by a child. (c) His theory could be understood by a child (d) His theory can be understood by a child

Options

A. His theory is being understood by a child
B. His theory can be understood by a child
C. His theory could be understood by a child
D. His theory was understood by a child

Answer

C