For Which of the Following Homogeneous Differential Equations Is the General

Multiple Choice

For which of the following homogeneous differential equations is the general solution given by
are arbitrary real constants?

A) $y^{(4) }+18 y^{\prime \prime}+81 y=0$
B) $y^{(4) }-18 y^{\prime \prime}+81 y=0$
C) $y^{(4) }+9 y^{\prime \prime}+81 y=0$
D) $y^{(4) }-81 y=0$
E) $y^{(4) }+81 y=0$