Concept:
For an inequality of the form
\[
\sqrt{A}\lt B,
\]
it is necessary that \(B\gt 0\). Then we can square both sides to obtain
\[
A\lt B^2.
\]
Step 1: Apply the condition \(2x+3\gt 0\).
Since
\[
\sqrt{x^2-12x+48}\ge 0,
\]
we must have
\[
2x+3\gt 0.
\]
Thus,
\[
x\gt -\frac{3}{2}.
\]
Step 2: Square both sides.
Given
\[
\sqrt{x^2-12x+48}\lt 2x+3,
\]
squaring,
\[
x^2-12x+48\lt (2x+3)^2.
\]
\[
x^2-12x+48\lt 4x^2+12x+9.
\]
\[
0\lt 3x^2+24x-39.
\]
\[
x^2+8x-13\gt 0.
\]
Step 3: Solve the quadratic inequality.
Factor roots using the quadratic formula:
\[
x=\frac{-8\pm\sqrt{64+52}}{2}
=\frac{-8\pm\sqrt{116}}{2}
=-4\pm\sqrt{29}.
\]
Hence,
\[
x^2+8x-13\gt 0
\]
gives
\[
x\lt -\sqrt{29}-4
\]
or
\[
x\gt \sqrt{29}-4.
\]
Step 4: Apply the restriction \(x\gt -\frac32\).
Intersecting
\[
(-\infty,-\sqrt{29}-4)\cup(\sqrt{29}-4,\infty)
\]
with
\[
\left(-\frac32,\infty\right),
\]
the first interval is rejected because
\[
-\sqrt{29}-4\lt -\frac32.
\]
Therefore, the solution set is
\[
(\sqrt{29}-4,\infty).
\]
\[
\boxed{(\sqrt{29}-4,\infty)}
\]
\[
\boxed{\text{Answer = (C)}}
\]