Which of these sentences is an example of a compound sentence?

a.

The interior designer spent hours perfecting her plan.

c.

The backyard was filled with both zinnias and begonias.

b.

The farmers planted so many crops, yet many were eaten by the pests.

d.

all of these

Without a doubt, the correct answer is:

The farmers planted so many crops, yet many were eaten by the pests.

B

Explanation:

A compound sentence is two separate thoughts that are connected by a conjunction.

So choice B works: "the farmers planted so many crops" and "many were eaten by the pests" are both sentences by themselves, so when you join them with a conjunction like "yet" and appropriate punctuation, it's called a complex sentence.

Why not A or C: You can't separate those into two distinct sentences. There also is no conjunction (for, and, nor, but, or, yet, so) in either one.