Which of the following differentiate between diffusion and effusion ?

Diffusion is the intermixing of the gas molecules at any direction and effusion is the reverse of diffusion 

Diffusion is the intermixing of the gas molecules, whereas effusion is the passage of gas molecules through the pores in one direction

Diffusion is the property of the gas molecules and effusion is the property of the gas container only 

Diffusion occurs at any direction, whereas effusion occurs under the potential difference