What was the main function of the protocell’s fatty acid membrane?
to allow sulfur dioxide to enter into the cell.
to allow the cells to communicate with each other.
to allow chemical compounds to enter into the cell.

The correct answer is - To allow chemical compounds to enter into the cell.

Explanation:

Protocells are the first cell-like structures that are produced by self-assembly of macromolecules in the membrane-bound spheres called microspheres which have the ability to divide and grow.

So protocells contained RNA ribozyme and fatty acid double membrane. The main function of protocell's fatty acid membrane was to allow the chemical compounds to enter the cell by membrane absorption so that the cell can grow and reproduce with the help of these organic compounds.

Later these reproducible cells may have selected by natural selection and they may evolve to produce prokaryotic cells.