Study the underlined part of each sentence. in which sentence does the verb agree with the subject? a. the astronauts in the space capsule has a lot of training. b. saturn, along with jupiter and uranus, have rings. c. the rings of saturn contain mostly ice and rock. d. the purpose of the missions are to find out more about mars.

The answer is C. "The rings of Saturn contain mostly ice and rock."

For A, notice that "astronauts" is plural, but "has" is singular.
For B, notice that "Saturn" is singular, and Jupiter and Uranus are not part of the subject, and "have" is plural.
For C, notice that "rings" is plural, and "contain" is plural.
For D, notice that "purpose" is singular, but "missions" is plural.