Pollution is
a usually necessary even though we don't like it
b sometimes necessary and can be managed
c never a good idea and should be avoided
d not desirable but can always be cleaned up

my good sir, your answer here is "jvhrwekjhvbebebjb"

your welcome.

the invasive species was introduced due to commercial purpouses, as there was a demand for fur clothes and hence, a business opportunity connected to this product. actually, it was when the nutrias scaped, causing harm to the us ecosystems when they acquired the status of invasive species. in this case they have caused an environmental problem, but it could have affected also economic interests or even human health.