9. The domain of definition of $f ( x ) = ( \log 2 ( x + 3 ) ) / ( x 2 + 3 x + 2 )$ is:\\
(A) $\mathrm { R } \backslash \{ - 1 , - 2 \}$\\
B) $( - 2 , \infty )$\\
(C) $\mathrm { R } / \{ - 1 , - 2 , - 3 \}$\\
(D) $( - 3 , \infty ) \backslash \{ - 1 , - 2 \}$\\