In which of the following insects is group instinct not displayed?

Analyze the question: We need the insect that does not show group (social) instinct, meaning it does not live in an organized colony with division of labour.

Concept: Social insects live in colonies with a caste system (queen, workers, soldiers, drones). They cooperate in feeding, defence, and reproduction. This cooperative behaviour is called group instinct.

Going through the options:

• A. Soldier ants: Ants live in colonies with castes (queen, workers, soldiers), so they show group instinct.
• B. Cockroaches: They are mostly solitary, with no caste system and no division of labour. They may gather in the same hiding places, but this is not organized social behaviour.
• C. Honey bees: They live in hives with a queen, workers, and drones, so they show group instinct.
• D. Termites: They live in colonies with a king, queen, workers, and soldiers, so they show group instinct.

Answer: Cockroaches are the insects that do not display group instinct, which is option B.

Exam tip: Remember the social insects with the acronym "ABT": Ants, Bees, Termites (and wasps). Whenever a question asks for the insect that is not social, look for the one outside this group. Cockroaches, grasshoppers, and houseflies are not social insects.