Answer:
D. cubic monomial
Explanation:
We are given the polynomial,

Since, we know,
Quadratic polynomial - is a polynomial with degree 2
Cubic polynomial - is a polynomial with degree 3
Also, we have,
Monomial - is a polynomial consisting of only one term
Binomial - is a polynomial consisting of two terms
Trinomial - is a polynomial consisting of three terms
As, we see that,
The polynomial
has degree 3 and consists of only one term.
So, the correct description for the given polynomial is 'cubic monomial'.
Hence, option D is correct.