A City Was Intensively Sprayed with DDT to Control Houseflies

question 44

Multiple Choice

A city was intensively sprayed with DDT to control houseflies. The number of houseflies was immediately greatly reduced. Each year thereafter, the city was sprayed again, but the flies gradually increased in numbers until 10 years later, when they were almost as abundant as they were when the control program began. Which explanation applies to this situation?

• A) Flies from other areas moved in and replaced the ones killed by DDT.
• B) The few flies that were affected by DDT but survived developed antibodies to DDT, which they passed on to their descendants.
• C) The DDT caused new mutations to occur in the surviving flies, resulting in resistance to DDT.
• D) The DDT killed most flies. The few that were already naturally resistant survived and passed this resistance on to their offspring.

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Definitions:

Correct Consensus Effect

The tendency of individuals to overestimate the extent to which their opinions, beliefs, preferences, values, and habits are normal and typical compared to those of others.

Opinion Effect

The impact that personal beliefs, judgments, or evaluations have on an individual's perception and decision-making.

Anima/Animus

In Jungian psychology, the unconscious or true inner self of an individual, the anima being the feminine aspect present in a male and animus the masculine aspect in a female.

Carl Jung

A Swiss psychiatrist and psychoanalyst who founded analytical psychology and introduced concepts like extroversion and introversion.