Sentence Correction

If current trends continue, by the year 2010 carbon emissions in the United States will soar to a level more than one-third higher than were those in 1990, according to official projections.

(A) will soar to a level more than one-third higher than were those
(B) will soar to a level more than one-third higher than that
(C) would soar to a level more than one-third higher than it was
(D) would soar to a level more than one-third higher than those
(E) would soar to a level more than one-third higher than they were

[spoiler]OA: B[/spoiler]

prediction is being done hence will is needed. c d e are out
a. "were those" is not needed.

"than that" in be does the proper comparison

Final solution at one place:

Important: The purpose of this post (and all the other posts by me) is to give a complete solution to all GMAT-Prep Verbal questions at one place. Sometimes students have to wade through dozens of posts to get to the final answer. My posts will give one complete and crisp solution required to arrive at the correct answer by eliminating the wrong one. Some of the content in these posts may have been taken from various other sources (discussion forums).

If current trends continue, by the year 2010 carbon emissions in the United States will soar to a level more than one-third higher than were those in 1990, according to official projections.
(A) will soar to a level more than one-third higher than were those
(B) will soar to a level more than one-third higher than that
(C) would soar to a level more than one-third higher than it was
(D) would soar to a level more than one-third higher than those
(E) would soar to a level more than one-third higher than they were

A word about conditionals:

If I meet her, I will tell her a story.

This is called a CONDITIONAL:

In this, we are talking about a "POSSIBLE" future - the action is NOT IMPROBABLE in future.

In this case, use the PRESENT + FUTURE (WILL) form.

So the sentence "If I meet her, I will tell her a story." Means that there is a positive possibility of my meeting her in the future...

Never use double future in such sentences:

If I WILL meet her, I WILL tell her a story. - WRONG.

But we may use the present tense in both parts if the context so demands:

If I meet her, I tell her a story.

In this case, 'if' means 'whenever'... this is correct construction.

***

If I met her, I would tell her a story.

If I were to meet her, I would tell her a story.

Were I to meet her, I would tell her a story.

All of these forms mean the same thing... there is no preference for one to another.

Even this form denotes FUTURE.

In this, we are talking about an almost "IMPOSSIBLE" future - the action is IMPROBABLE in future.

In this case, use the

PAST + WOULD form

Or If + were + would form

Or Were + Would form....

So the sentence "If I met her, I would tell her a story." Means that there is a hardly any possibility of my meeting her in the future...

SIMILARLY the sentence "If I were to meet her, I would tell her a story." Means that there is a hardly any possibility of my meeting her in the future...

Similarly the sentence "Were I to meet her, I would tell her a story." Means that there is a hardly any possibility of my meeting her in the future...

In all "wish" sentence, the above structures are used.

****

If I had met her, I would have / could have told her a story.

≡ Had I met her, I would have / could have told her a story.

This sentence is not about FUTURE... this is about PAST that could not happen...

We always use

"If + had + would / could have" form OR

"HAD + would / could have" form here

In the given sentence, we are talking about 'future' with respect to 'present'. In this case, 'will' is the correct usage. 'Would' is correct when the future is talked about with respect to 'past'. This eliminates C, D, and E.

Here the comparison is for the levels ... so 'will soar to a level more than one-third higher than that (the level) in 1990 ... brings out the correct comparison in B.

Choice A uses 'those (plural)' to refer to 'level (singular)' ... wrong. Also, A is not parallel ('were' is not parallel to any preceding word).

B: correct