Question

milkweeds are plants that produce toxic, bittertasting chemicals. some insects have developed the ability to safely feed on milkweed. they accumulate some of the toxin in their bodies, causing them to taste bitter to other animals that may try to eat them. as a result, most animals avoid eating these insects. a possible explanation for this relationship is that

1. eating a toxic plant increases the ability of these insects to survive and reproduce
2. milkweed populations are controlled by many insects
3. the milkweed benefits from the insects that can tolerate the toxin they produce
4. eventually the insects will become immune to the toxin

Explanation:

To solve this, we analyze each option:

• Option 1: Insects that can eat milkweed (toxic) accumulate the toxin, making them unpalatable to predators. This increases their survival (since predators avoid them) and thus their ability to reproduce. This fits natural selection/evolutionary concepts in biology.
• Option 2: The passage is about insects' adaptation, not milkweed population control by insects. Eliminate.
• Option 3: The passage focuses on insects' benefit, not milkweed's benefit from insects. Eliminate.
• Option 4: The insects already feed on milkweed (tolerate toxin), and the question is about the relationship's explanation, not future immunity. Eliminate.

Answer:

1. eating a toxic plant increases the ability of these insects to survive and reproduce