A few years ago, scientists began studying the microbial life of our stomachs. Called The American Gut project, this study aims to understand the life of the bacteria that live in our digestive system. According to an article in the New York Times by Michael Pollan, the goal is to gather information on the types and amounts of bacteria in the human gut. Scientists want to describe what a normal healthy microbe and human relationship should look like inside our digestive system. While the research is still in the very early stages, scientists have learned the following: The strongest and healthiest microbe systems are those with a lot of variety.
The guts of Americans have much less variety than the guts of other populations.
Diets that include a lot of processed foods support less variation in bacteria.
Which of the following best summarizes the main point of the third paragraph and list? (7 points)

a
A healthy microbe to human relationship is a balance we can study and understand.
b
Human guts tend to gather a range of microbes that maintain health.
c
New studies suggest a wide variety of microbes is best for the human body.
d
The American Gut project is a study to understand the digestive system.