Below is a diagram of the water cycle. Local environmental scientists have collected evidence of the presence of multiple insecticides in the river. Insecticides are used on crops to help prevent crop damage from insects.

Question

Which step of the water cycle most likely contributes to the presence of insecticides in the river?

Responses
A Step ZStep Z
B Step YStep Y
C Step XStep X
D Step WStep W

Answer 1

To determine which step of the water cycle most likely contributes to the presence of insecticides in the river, consider how insecticides might enter the water system.

Insecticides are typically applied to crops, and when it rains, runoff can occur, leading these chemicals to wash into nearby rivers and streams. This type of contamination is most commonly associated with precipitation or runoff.

Although I don't have the specific diagram you're referencing, here’s a general idea of the steps:

• Step W: Evaporation
• Step X: Condensation
• Step Y: Precipitation
• Step Z: Runoff

Given this context, the step that would most likely contribute to the presence of insecticides in the river would be:

D: Step W (Runoff)

This step represents the movement of water (and any contaminants like insecticides) from the land into the waterways.