I think the first option is the answer.
Explanation:
Cell membranes are selectively permeable. Some solutes cross the membrane freely, some cross with assistance, and others do not cross at all. A few lipophilic substances move freely across the cell membrane by passive diffusion. ... Large molecules do not cross intact cell membranes, except in certain special cases.
The ostrich doesn't strictly live in one biome, while it is true that they live in a warmer, dryer climate most of the time. But they are also known to live in colder regions as well, they live a nomadic lifestyle, as long as they can find food and water they can live happily.
Hope this helps!
Can you put the terms as well, please