in cases of hydrogen atom, whenever a photon is emitted in the Balmer series, (a)there is a probability emitting another photon in the Lyman series
(b) there is a probability of emitting another photon of wavelength `1213 Å`
(c ) the wavelength of radiaton emitted in Lyman series is always shorter then the wavelength emitted in the Balmer series
(d) All of the above.