Select the sentence with a clause used as a predicate noun. the man who came here yesterday was selling magazines. we left the performance early because we were tired. the reason he opened the door was that the princess pointed to it.

The correct answer is C.

A predicative noun is one that comes after a linking verb.

In this case, "that the princess pointed to it," is a phrasal verb actining as a noun following the linking verb "was."

In options A and B, "was" and "were" are part of verbal phrases and are not acting as linking verbs.

the president was the speaker and it was a great part of history.

explanation:

video of the national aeronautic space administration's (nasa) coverage of president john f. kennedy’s address at rice university, houston, texas, concerning the nation's efforts in space exploration. in his speech the president discusses the necessity for the united states to become an international leader in space exploration and famously states, "we choose to go to the moon in this decade and do the other things, not because they are easy, but because they are hard."

nominative