Answer:
A.

Explanation:
We have to find the expression which is tri-nomial.
Trinomial: It is that expression which contains three terms.
A.

It contains three terms .Therefore, it is trinomial.
B.4xyz
It does not contains three terms .Therefore, it is false.
C.

It does not contains three terms .Therefore, it is false.
D.

It contains four terms .Therefore, it is not trinomial.
Answer:A.
