The question is:
What is the main difference between a prokaryotic cell and an eukaryotic cell?

The choices are

a. Only prokaryotic cells have vacuoles







b. Eukaryotic cells are smaller than prokaryotic cells







c.Prokaryotic cells have many organelles, each with their own specialized functions







d.Only eukaryotic cells have its genetic material surrounded by a membrane.

a. is not the answer. Guess how I know that. I looked it up!

Please check your textbook or classnotes or go online for the correct choice. (We don't do your homework for you, and want you to show some effort.)

The question is:
What is the main difference between a prokaryotic cell and an eukaryotic cell?

The choices are

a. Only prokaryotic cells have vacuoles
b. Eukaryotic cells are smaller than prokaryotic cells
c.Prokaryotic cells have many organelles, each with their own specialized functions
d.Only eukaryotic cells have its genetic material surrounded by a membrane.

So you have a multiple choice assignment. You can guess and have a 25% chance of getting it right, or you can go back to your textbook, read, and understand what is going on. Not a matter of memorization but understanding of what a cell is how everything works.