Step 1: Understanding the BMD Curve.
The degree of the bending moment diagram (BMD) curve is directly related to the load intensity. For a load intensity that is of degree \(n\), the bending moment curve degree will be \(n + 1\).
Step 2: Conclusion.
Therefore, the correct degree of the BMD curve is \(n + 1\), making option (2) the correct answer.
Final Answer:
\[
\boxed{n + 1}
\]