Choose the expression that represents a quadratic expression.
a/ 6x4 − 5x3 + 3x2 −7x − 8. b/5x3 + 3x2 −7x − 8. c/2x2 + 3x − 1. d/3x − 1

C. 2x2 + 3x − 1 is quadratic

Step-by-step explanation:

Quadratic expressions are polynomial expressions in which the highest power of the variable is 2.

Looking at option A, the highest power of the variable in the polynomial is 4. Therefore, it is not a quadratic expression.

Looking at option B, the highest power of the variable in the polynomial is 3. Therefore, it is not a quadratic expression.

Looking at option C, the highest power of the variable in the polynomial is 2. Therefore, it is a quadratic expression.

Looking at option D, the highest power of the variable in the polynomial is 1. Therefore, it is not a quadratic expression.