A.
$\varphi_{11}''+2\varphi_{21}''e^x+\varphi_{22}''e^x+\varphi_2'e^x$;
B.
$\varphi_{11}''+2\varphi_{12}''+\varphi_{22}''e^x+\varphi_2'$;
C.
$\varphi_{11}''+\varphi_{21}''e^x+\varphi_{22}''e^{2x}+\varphi_2'e^x$;
D.
$\varphi_{11}''+2\varphi_{12}''e^x+\varphi_{22}''e^{2x}+\varphi_2'e^x$.