As environments change, some organisms become endosymbiotic, which is to say, organisms are able to live within the body or cells of another organism. Which feature of protists is probably endosymbiotic in origin?
cysts
В
microtubules
С
a nucleus
D
mitochondria

significant amounts of nitrogen oxides, carbon monoxide, and other pollution

explanation:

passenger vehicles are a major pollution contributor, producing significant amounts of nitrogen oxides, carbon monoxide, and other pollution. in 2013, transportation contributed more than half of the carbon monoxide and nitrogen oxides, and almost a quarter of the hydrocarbons emitted into our air.

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