Step 1: Recall the effect of negative feedback.
Negative feedback feeds a portion of the output back to the input in opposite phase.
Step 2: Identify its advantages.
Negative feedback
\[
\begin{aligned}
&\checkmark\ \text{reduces gain},
&\checkmark\ \text{reduces distortion},
&\checkmark\ \text{improves stability},
&\checkmark\ \text{reduces noise},
&\checkmark\ \text{increases bandwidth}.
\end{aligned}
\]
Hence,
\[
\boxed{\text{Decreased gain and reduced distortion}}
\]
Therefore,
\[
\boxed{(A)}
\]
is the correct answer.