The bed is made . . . . . . . . wood. A. by B. of C. from D. with

by
of
from
with

The correct answer is B. of.

The preposition “of” is used to indicate the material that something is made of. In this case, the bed is made of wood.

The other prepositions could be used in different contexts. For example, “by” could be used to indicate the person who made the bed, “from” could be used to indicate the place where the wood came from, and “with” could be used to indicate the tools that were used to make the bed.