Find real$-$valued fundamental solutions y$1($t$)$y$1($t$)$ and y$2($t$)$y$2($t$)$ of the differential equation

y$+$$2$y$=0,$y$+$$2$y$=0,$

where is a positive constant.

A$.$y$1($t$)=$etandy$2($t$)=$tety$1($t$)=$etandy$2($t$)=$tet

B$.$y$1($t$)=$cos$($t$)$andy$2($t$)=$sin$($t$)$y$1($t$)=$cos$($t$)$andy$2($t$)=$sin$($t$)$

C$.$y$1($t$)=$eitandy$2($t$)=$e$$ity$1($t$)=$eitandy$2($t$)=$e$$it

D$.$y$1($t$)=$etcos$($t$)$andy$2($t$)=$etsin$($t$)$y$1($t$)=$etcos$($t$)$andy$2($t$)=$etsin$($t$)$

E$.$y$1($t$)=$etandy$2($t$)=$e$$ty$1($t$)=$etandy$2($t$)=$e$$t

F$.$y$1($t$)=$cos$($$2$t$)$andy$2($t$)=$sin$($$2$t$)$y$1($t$)=$cos$($$2$t$)$andy$2($t$)=$sin$($$2$t$)$

G$.$y$1($t$)=$etcos$($$2$t$)$andy$2($t$)=$etsin$($$2$t$)$y$1($t$)=$etcos$($$2$t$)$andy$2($t$)=$etsin$($$2$t$)$

H$.$None of the above.