The groups of small cells better than one large cell at moving material in and out because they have a greater surface-to-volume ratio.
Option: A
Explanation:
This happened so as these smaller cells, unlike bigger cells, can quickly and willingly enter and move through the membranes of other cell membranes and permeable coverings. For these smaller and mini cells, it is also important to penetrate and move effectively, distribute and transport products and materials such as nutrients, oxygen and waste across the body without requiring enough energy and saving less space. They are cheaper, more effective and use less room for simple reasons, and most notably deplete less resources.
