Answer:
D. Quartic trinomial
Explanation:
Given polynomial:

We can make following conclusions for the given polynomial.
1) The polynomial has three terms including a constant term. Thus it is a trinomial as trinomials are polynomials with 3 unlike terms.
2) The leading term is
as it is the highest degree term..
3) The degree of polynomial is 4 as leading variable
in the leading term is raised to power of 4. Thus, it is a quartic polynomial as it is of degree 4.
Thus, this polynomial can be called a quartic trinomial.