In which sentence is the predicate nominative correct? a the actors in the play are them. b my best friend is her. c it is them and me in the picture. d the loudest singers are they.

Horrible as it may sound to you, the correct answer is D. Or it was in my day of learning this stuff. Of course my grammar teacher would have kept the whole class in detention for a month if we dared say "to boldly go" was correct. She was tough.

Predicate nominates are related to objects. They are used with linking verbs which are -- is are have etc. They have the strange property of agreement with the subject. So It is me is not correct. Me is an object word. You use me in a sentence like It took me an hour to wash the dishes.

The correct form is It is I who wishes to speak to you. I wish to speak to you is the way you think of it.

D can by made more understandable and less horrid to your ear by saying

They are the loudest singers.

All they other answers are wrong. They should be using they not them which is pretty awful.

4,7

explanation: