I think the answer is 3 and 4
Fitness.
Explanation:
Fitness is a relative thing.A genotypes' fitness include its ability to survive,find a mate,produce off spring.
B. A form of energy coupling refers to using the release of energy from exergonic hydrolysis of ATP to initiate other endergonic reactions for cellular metabolism.
Answer:
it is because there is less oxygen and creatures need more oxygen to perform their work..
hope this helps you ☺️☺️