Which of the following pair will diffuse at the same rate?

Which of the following pairs will diffuse at the same rate through a porous plug ?

Which of the following pairs will effuse at the same rate through a porous plug .

Which of the following pair of gases will have same rate of diffusion under similar conditions?

Which of the following pair of gases will have same rate of diffusion under similar conditions?

The atomic weights of carbon, nitrogen and oxygen are 12,14 and 16 respectively. Among the following pairs of gases, the pair that will diffuse at the same rate is :

Which of the following sets consist of gases with same rate of diffusion?