In the 1800s humans hunted elephant seals in the arctic. At one point, the wild
population of seals was reduced to only 20 individuals, greatly reducing the gene
pool.
As elephant seals have reproduced and recovered from danger, this sudden
shrinkage of the gene pool would be classified as __
O A catastrophic event
O A bottleneck event
A mutation event
The founder's effect

A bottleneck event.

Explanation:

A population bottleneck is an event that drastically reduces the size of a population. The bottleneck may be caused by various events, such as an environmental disaster, the hunting of a species to the point of extinction, or habitat destruction that results in the deaths of organisms.

Hope this helps!

answer: ice crystals in air

the water from the water body or another source of water gets evaporated as water vapor as an effect of heat on water. these water vapor rises in the upper layers of the earth atmosphere under high atmospheric pressure. the atmospheric pressure of these water molecules starts to decrease due to the effect of cold air. the invisible water vapor condenses into visible water droplets and ice crystals.these ice crystals and water droplets being less denser than the surrounding air floats on air as clouds.