Which of the following have been changed or altered due to climate change.
A. Droughts
B. Flooding
C. Melting of polar ice caps
D. All of the above

D.

Explanation:

Droughts come from an intense increase in temperature. This causes water/moisture to evaporate from the ground. This is caused by greenhouse gas emissions which makes things a lot warmer. Thus, the temperature rises.

C and B are linked. The icecaps melt which cause the water levels to rise. When the icecaps melt, the water goes into the ocean and causes a rising in the sea level, thus meaning floods can happen.

weathering is the answer.

"1. it should be, it has been for about 20 years, and it's really not much different in the end than breeding animals to have particular traits. there are always concerns about genetically engineered animals/plants affecting the environment in unexpected negative ways, but i can't think of an example where the fears didn't turn out to be baseless.  

first, as you point out, it would be a great advance in pharmacology, to be able to tailor drugs and their doses to me. the pros involve better medical treatment. the cons involve privacy issues like insurance companies denying coverage to people with genetic risk factors. looking at dna markers wouldn't affect the frequency of genetic diseases, but it would allow detection of them earlier. and ok, actually i suppose that if people used this information to avoid having children with genetic diseases, some might decrease in frequency."