Answer:
chemicals, disease, obesity
Explanation:
Chemicals are often thought of as dangerous. Disease is obviously a bad thing, and obesity is a health risk. The words "affordably" and "attainable" generally have a positive connotation, and affordability is nice and people attain positive things.
Carbon is added to the environment just by humans and higher animals breathing in oxygen and breathing out carbon dioxide. But by far the biggest contributor of carbon to the environment especially the atmosphere is the burning of fossil fuels which then contribute to the greenhouse gases which in turn cause global warming. Water vapour, carbon dioxide, methane and ozone are the main constituents of greenhouse gas.
Stated
it says to improve the air quality