In which sentence is the predicate nominative correct?
a.
this is he.
b.
this is him.
c.
it is them.
d.
it is her.

My necktie rich and modest, but asserted by a simple pin-[they will say: "but how his arms and legs are thin! "]do i daredisturb the universe? in a minute there is timefor decisions and revisions which a minute will reverse.which lines indicate that the speaker is concerned about what others think of him? my morning coat, my collar mounting firmly to the chin,my necktie rich and modest, but asserted by a simple pin-in a minute there is timefor decisions and revisions which a minute will reverse.o with a bald spot in the middle of my hair[they will say: "how his hair is growing thin! "]and indeed there will be timeto wonder, "do i dare? " and, "do i dare? "

Plz change it i can not change this sentences .

What is a mechanism by which organisms maintain homeostasis when the level of one substance influences the level of another substance or the activity of an organ.