Atomic Structure: JEE Main 2019 Chemistry question

Heat treatment of muscular pain involves radiation of wavelength of about 900 nm. Which spectral line of H atom is suitable for this purpose? [R_H = 1 $\times$ 10⁵ cm^–1, h = 6.6 $\times$ 10^–34 Js, c = 3 $\times$ 10⁸ ms^–1]