Which one of the following reactions will give NO (nitric oxide) gas as one of the products?

• A. 3Cu + 8HNO3 (dilute) →
• B. Cu + 4HNO3 (conc.) →
• C. 4Zn + 10HNO3 (dilute) →
• D. Zn + 4HNO3 (conc.) →