Fact 1: Bottleneck effect occurs when a population suddenly gets much smaller.

Fact 2: Fishing pressure is relatively low due to a smaller human population.

Given the two facts above, answer the question "What can make the bottleneck effect occur in fish?" with the following options: 
- increased habitat
 - acid rain
 - humans
 - Winter
 - increased food
 - storms
 - increased resources
 - Toxicity


 

   humans      