According to the Selection Rules, Which of the Following Transitions

Multiple Choice

According to the selection rules, which of the following transitions is not allowed?

A) n = 3, ℓ = 2 to n = 2, ℓ = 1
B) n = 4, ℓ = 3 to n = 3, ℓ = 2
C) n = 3, ℓ = 1 to n = 1, ℓ = 0
D) n = 2, ℓ = 1 to n = 1, ℓ = 0
E) n = 4, ℓ = 2 to n = 3, ℓ = 2