Which of the following is a common pest found in human hair?

Crab lice, also known as pubic lice, are specifically adapted to live in human hair, particularly in coarse hair areas such as the pubic region. They are small, parasitic insects that feed on human blood and are transmitted primarily through close personal contact. While they can occasionally be found in other hair-bearing areas of the body, their primary association is with human hair, making them a notable presence in discussions about pests that infest humans.

Fleas are more commonly associated with pets and their environments, as they primarily infest animals and occasionally transfer to humans. Ticks are primarily found in outdoor environments and are more associated with animals than with hair. Bedbugs are known for infesting bedding, furniture, and personal belongings but do not live in hair. Therefore, the unique life cycle and habitat preferences of crab lice make them the correct choice when identifying a common pest specifically found in human hair.