Identify the choice that best describes the sentence.

Galileo the first astronomer to use a telescope, confirmed the theory that the earth and planets circle the sun.

A - Simple.

B - Compound.

C - Complex.

D - Compound - complex.

C - Complex

The sentence is a complex sentence because it contains two predicates. These two predicates are: "confirmed" (an independent clause) and "circle" (a dependent clause). A complex sentence refers to any sentence that contains at least one dependent or subordinate clause.