GMAT Prep SC Question

elliefrance wrote:Need help with this one -

Q: Currently 26 billion barrels a year, world consumption of oil is rising at a rate of 2 percent annually.

- same
- the world is consuming oil at an increasing rate of
- the world's oil is being consumed at the increasing rate of
- the rise in the rate of of the world's oil consumption
- oil is consumed by the world at an increasing rate of

I thought it was E because I needed the word after the opening clause to talk about the oil, but E is incorrect. Can anyone explain to me why A is the right answer?

Thanks!
-Ellie

whats_in_the_store wrote:"26 billion barrels a year" is modifying consumption and not world, wouldn't it be better if it were in possessive! Something like "world's consumption"?