GKFix MCQ Question

What is the expression for frequency (ν) associated with photon emission or absorption?

• A. ν = 3.29×10¹⁵ (1/nf² – 1/ni²) Hz
• B. ν = 3.29×10¹⁵ (ni² – nf²) Hz
• C. ν = 3.29×10¹⁵ (nf² – ni²) Hz
• D. ν = 3.29×10¹⁵ (1/ni² – 1/nf²) Hz