Answer: The answer is (D) cubic monomial.
Step-by-step explanation: The given polynomial is

We are to select the correct description of the above polynomial from the given options.
Since there is only one term in the polynomial, so it is a monomial.
Also, the power of the unknown variable is 3, so the degree of the polynomial is 3 and so it is a cubic polynomial.
Therefore, the given polynomial is a cubic monomial.
Thus, (D) is the correct option.