What Is the Two-Parameter Family of Solutions of the Second-Order $y=\frac{21}{16} x^{2}+C_{1} x^{\frac{6}{7}}+C_{2}$

Multiple Choice

What is the two-parameter family of solutions of the second-order differential equation

A) $y=\frac{21}{16} x^{2}+C_{1} x^{\frac{6}{7}}+C_{2}$
B) $y=C_{1} x^{2}+C_{1} x^{-6}$
C) $y=C_{1} x^{2}+C_{1} x^{\frac{6}{7}}$
D) $y=\frac{21}{16} x^{2}+C_{1}+C_{2} x^{-6}$