#### Answer

Polynomial; Degree of 11; None of these

#### Work Step by Step

A polynomial is a term or finite sum of terms with only positive or zero integer exponents. 15$a^{2}b^{3}$ + 12$a^{3}b^{8}$ - 13$b^{5}$ + 12$b^{6}$ is a polynomial but has four terms, so it is neither a monomial, binomial, nor trinomial. Its degree is 11 because the term with the largest degree is 12$a^{3}b^{8}$, and by adding the exponents we get the degree: 3 + 8 = 11