Question

If there are only a few remaining members of an insect species living in one area, which would most likely cause this species to become extinct?

the introduction of new predators to the insects’ environment
a genetic mutation in an individual that causes it to be very small
a disease that causes a mother insect to die shortly after laying eggs
the introduction of a new food source to the insects’ environment

Answer 1

The introduction of new predators to the insects’ environment.

Rationale: A small, localized population is especially vulnerable to new predators that can quickly wipe out the remaining individuals. A mutation in a single individual or a new food source is unlikely to cause extinction, and a disease that kills mothers after laying eggs might not immediately stop reproduction (and is less certain to eliminate the entire population than a new predator).