A fifth-degree polynomial equation with rational coefficients has the roots 3, 8i, and 7- radical 5. Which are also roots of the polynomial equation?

Using complex numbers and radicals, it is found that the correct option is C.
When a complex number is a root of a polynomial function, it's conjugate also has to be.
The same is valid for radicals, as they are in the [tex]\pm[/tex] format.
Hence, option C is correct.
For more on complex numbers and radicals, you can check https://brainly.com/question/25173944