The best answer to go with is b you’re welcome
The answer is B to your question
Cell walls are supporting structures that help the plant to have a fixed shape and protect it from injury,animal cells do not need to keep the structures because they have the skeletal system to protect the organs and cushion them against any external injuries.
The answer is that a unicellular organism would swell and burst.
In a hypotonic solution the water concentration of the cell's cytoplasm is lower then that of the hypotonic solution. If unicellular organism is exposed to a hypotonic solution, the water from the solution will enter the organism by the process called osmosis. The aim is to balance water concentration on the inside and outside of the organism. But, that water entering the cytoplasm of the cell will make pressure on the cell membrane. If the excess water cannot be removed from the organism, it will swell and burst.