What is the main idea of this selection?
A) Though some microbes can make people ill, many are quite helpful to humans.
B) Scientists have recently discovered microbes in and on the human body.
C) Microbes benefit people and the planet by cleaning up oil in the oceans.
D) Microbes are too small to see without using a powerful microscope.
What is the main idea of this selection?
Share
The correct answer is A) Though some microbes can make people ill, many are quite helpful to humans.
Explanation: This option encapsulates the main idea that highlights the dual nature of microbes—while acknowledging their ability to cause illness, it emphasizes the helpful roles they play in human health and the environment. The other options present specific facts rather than the overarching theme of the selection.