Step 1: Domain Condition
The expression is a real number if the denominator is not equal to zero.
Step 2: Factoring the Denominator
$x^{3} + 4x^{2} + 3x = x(x^{2} + 4x + 3) = x(x + 3)(x + 1)$.
Step 3: Finding Zeros
The denominator is zero when $x = 0$, $x = -3$, or $x = -1$.
Step 4: Conclusion
Therefore, $x$ can be any real number except $\{0, -1, -3\}$.
Final Answer: (c)