The mass of an oxygen molecule is about 16 times that of a hydrogen molecule. At room Temperature the rms speed of oxygen molecules is v. The rms speed of the hydrogen molecules at the same temperature will be
4v
v = √3kTM. Therefore, v0 = √3kTM0 and vh = √3kTMh
Thus, v0vh = MhM0 = √116 = 14
Or vh = 4v0
Hence, the correct choice is (c)