Which of These Is a Fundamental Set of Solutions for the Differential

Multiple Choice

Which of these is a fundamental set of solutions for the differential equation
Select all that apply.

A) $y_{1}=\cos (10 t)$ and $y_{2}=\sin (10 t)$
B) $y_{3}=7 \cos (10 t) -20 \sin (10 t)$ and $y_{4}=10 \cos (10 t) -14 \sin (10 t)$
C) $y_{5}=e^{-10 t}$ and $y_{6}=e^{10 t}$
D) $y_{7}=e^{10 t} \sin (10 t)$ and $y_{8}=e^{10 t} \cos (10 t)$
E) $y_{9}=7 \sin (10 t)$ and $y_{10}=7 \sin (10 t) -8 \cos (10 t)$