How does importing coal contribute to pollution?
a. if the u. s. did not import coal, it would have to use alternative fuel methods
b. fuel is used to transport the coal, which contributes to pollution.
c. shipping coal overseas causes water pollution from coal spills.
d. all of the above

I'm not absolutely sure, but I think it's either B or D.

I think that A is more of a positive contribution, and it doesn't even explain how it contributes to pollution.  And as for C, I don't think that coal causes water pollution when spilled into the ocean; that's more rather oil.  B sounds like it is the most legitimate answer.

I really hope this helps!  Let me know what the answer is.  :)

B

Explanation:

i took a guess from the person above and they were right on B.

lysosome is this part of the cell is surrounded by a very thick outer membrane to protect the rest of the cell from its strong enzymes.

"do a testcross with a homozygous recessive plant."