The Wavelength of Light Associated with the N = 2 $\times$

Multiple Choice

The wavelength of light associated with the n = 2 to n = 1 electron transition in the hydrogen spectrum is 1.216 $\times$ 10^-7 m.By what coefficient should this wavelength be multiplied to obtain the wavelength associated with the same electron transition in the Li²⁺ ion?

A) 1/9
B) 1/7
C) 1/4
D) 1/3
E) 1