Question

by which mechanism would a steroid molecule diffuse into the cell?

Explanation:

Steroid molecules are lipid - soluble. They can pass through the lipid - bilayer of the cell membrane without the help of transport proteins. Image A represents simple diffusion which is how lipid - soluble substances like steroid molecules diffuse into the cell. Images B and C show facilitated diffusion with the help of carrier and channel proteins respectively, which is not applicable for steroid molecules.

Answer:

A.