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, what can make the bottleneck effect occur in fish?

Choose your answer from:
1). increased habitat;
2). acid rain;
3). humans;
4). Winter;
5). increased food;
6). storms;
7). increased resources;
8). Toxicity;
Answer:
3).