Which one of the following belongs to the family Muscidae?

The question asks which of the listed insects belongs to the family Muscidae.

First, we examine each option:

• Cockroach – belongs to the order Blattodea and family Blattidae, not Muscidae.

• House fly – scientifically known as Musca domestica. The genus Musca is the type genus of the family Muscidae, so the house fly is a member of this family.

• Fire fly – actually a common name for certain beetles in the family Lampyridae (fireflies), not Muscidae.

• Grasshopper – belongs to the order Orthoptera and family Acrididae, unrelated to Muscidae.

By comparing the taxonomic classification of each option, only the House fly is classified within the family Muscidae.

Therefore, the correct answer is House fly.