Answer: A, burning fossil fuels
The best answer is A. The purpose of the cell wall is to hold the cell in a specific shape, usually rectangular or square. For example, a plant cell's wall keeps it rigid so that the plant can stand up.
If the cell does not have a wall, it can easily change shape to accommodate for things coming in and out of the cell.
Hope this helps!
Answer:
The answer is B
Explanation:
New species often form on new islands because they evolve to fill new niches
The answer is "B. Marsupials". Marsupials undergo relatively premature births compared to many other species, and although this puts the baby at risk, it lessens the risks for the mother.