1. When is a rational algebraic expression in lowest term?

A. If the numerator and denominator are both of degree one.
B. If either the numerator or the denominator is factored completely.
C. If the numerator and denominator have no common factor other than 1.
D. If the numerator and denominator have no common factor other than -1.

2. Which of the following is one of the steps in simplifying rational expressions?

A. Add the common factors.
B. Multiply the common factors.
C. Divide out the common factors.
D. Subtract out the common factors.