Final answer:
A polynomial quintic trinomial is a polynomial of degree five with three distinct terms, which indicates that its highest power is five and it consists of three terms.
Step-by-step explanation:
A polynomial quintic trinomial is a specific type of polynomial expression. To break it down, 'polynomial' refers to a mathematical expression involving a sum of powers in one or more variables multiplied by coefficients. A 'quintic' indicates that the highest power of the variable is five, which means the polynomial is of degree five. Finally, 'trinomial' specifies that the polynomial has three distinct terms. Therefore, the correct answer to what a polynomial quintic trinomial is: c) A polynomial of degree five with three terms. As a comparison, quadratic functions, which are also polynomials, are specifically second-order polynomials (degree two) with potentially three terms, but a quintic trinomial is fifth-order.