Question

Which word in the sentence is a plural pronoun?

Answer 1

We is the plural pro noun

Answer 2

(First, I guess you chose the wrong subject since this is English not Physics :p)
Now, the pronouns are words that take the place of a noun.
The Personal pronouns are: I, you, he, she, it, we, they.
I, you, he, she, it are singular; while we and they are plural.
So, in the sentence, we can clearly see the pronoun "we", which is a plural pronoun.
So the plural pronoun in this sentence is We (Answer D)

Hope this Helps! :)