Vitamin C deficiency leads to scurvy, which causes bleeding gums and weakness.
Step 1: Analyze the options.
- Rickets — Vitamin D deficiency
- Scurvy — Vitamin C deficiency ✔
- Night blindness — Vitamin A deficiency
- Beriberi — Vitamin B₁ deficiency
Step 2: Conclusion.
Hence option (B) is correct.
Final Answer:
\[
\boxed{(B)}
\]