Use a change of variables to evaluate the following definite integral. Integral from 2 to 3 StartFraction 2 x Over left parenthesis x squared plus 4 right parenthesis cubed EndFraction dx Question content area bottom Part 1 Determine a change of variables from x to u. Choose the correct answer below. A. uequals left parenthesis x squared plus 4 right parenthesis cubed B. uequals 2x C. uequals x squared plus 4 D. uequals x squared