Animals in the tundra have thick fur and lots of body fat to keep them warm.

Which limiting factor is this adaptation a response to?

Animals must climb many tall trees to find food in the tundra.

There is very little oxygen in the tundra.

Water in the tundra is not salty enough.

The temperature in the tundra is freezing.

The temperature in the tundra is freezing.

Explanation:

If the tundra is freezing, then they will obviously need an adaptation that will help them keep warm.

b. He figured out and explained how these changes happened and supported his ideas with evidence

Explanation:

Darwin, through his studies as a naturalist on the voyage of HMS Beagle was able to figure out how evolution occur and explained the changes that happened with several supportive evidence.

During the exploration, Darwin participated in several studies including anatomical, morphological, and paleontologist studies after which he published his books on 'The origin of life'.

In the book, Darwin explained how organism evolve with time and he was able to support his hypotheses with multiple evidence. He later formed the theory of natural selection based on his studies.

The correct option is b.