B. 2 times the natural log of the quantity x plus 1 plus 2 times x divided by the quantity x plus 1
C. 2x(x + 1)(2x - 1)
D. the product of the quantity 2 times the natural log of the quantity x plus 1 plus 2 times x divided by the quantity x plus 1, and the quantity x plus 1 raised to the 2x power