The diagram shows a food web. A flowchart. Cycle 1. 1, Grass. 2, Grasshopper. 3, Shrew or Mouse. 4, Fox. Cycle 2: 1, Grass. 2, Mouse. 3, Fox or Snake. Cycle 3: 1, Grass. 2, Rabbit. 3, Fox.

What would most likely happen to the food web if the amount of grass drastically decreased?

The mouse and grasshopper would be affected.
Only the rabbit would be affected.
The grasshopper, mouse, and shrew would be affected.
The entire food web would be affected.

answer; i believe the correct answer is (a)0

"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."