Official ExplanationBased on the most recent carbon emission numbers, the United States emits over five billion metric tons a year,
but the emissions are higher in some countries and lower in others.A. but the emissions are higher in some countries and lower in othersB. but these emissions are higher in some countries; lower in othersC. although in some countries, it is higher and in others it is lowerD. although this is more in some countries and less in othersE. although it is more than that in some countries and less than that in othersA review of our answer choices shows there are several options for the subject of the clause (the/these emissions, it, and this). We also have to choose between higher/lower and more/less. There is a split between “although” and “but” to start the clause.
It might be tempting to want to narrow down options by focusing on whether we should use “but” or “although,” but we should avoid that temptation. There is some subjective reasoning and opinion about the “rules” for using one over the other, and on the GMAT, we want objective reasoning.
Let’s just look at each answer choice one by one. The modifying phrase at the beginning of the non-underlined portion tells us this sentence is talking about carbon emissions, but once we know that, we can ignore that phrase and just start with the subject “the United States.”
Option A: The United States emits over five billion metric tons a year, but the emissions are higher in some countries and lower in others.This sentence has two independent clauses joined by a coordinating conjunction (but). The subject of the second clause is “the emissions,” which refers back to carbon emissions, and it makes sense with the rest of the sentence. Emissions is a countable noun, and higher and lower are used with countable nouns. This sentence seems correct, but we still need to review the other choices.
Option B: The United States emits over five billion metric tons a year, but these emissions are higher in some countries; lower in others.The semicolon in front of lower creates a phrase that is just a fragment. We cannot have a fragment just hanging off the end of a sentence. Also, “these” emissions makes it seem like it is specifically referring to the carbon emissions from the U.S. that are higher or lower in another country. The number of carbon emissions in the U.S. wouldn’t change from country to country. The emission of those countries could be higher than lower than those of the U.S., but the U.S. numbers won’t change. This sentence is illogical and grammatically incorrect. It cannot be the correct answer.
Option C: The United States emits over five billion metric tons a year, although in some countries, it is higher and in others it is lower.“It” as the subject makes this sentence too vague. What is “it”? The carbon emissions of those countries, the carbon emissions of the U.S., or the number five billion? The sentence is unclear and could potentially be saying the number five billion is lower in some countries and higher than others. Five billion is five billion. This cannot be the best answer.
Option D: The United States emits over five billion metric tons a year, although this is more in some countries and less in others.Once again, having “this” as the subject leaves us questioning what its antecedent is—the carbon emissions of those countries, the carbon emissions of the U.S., or the number five billion? The sentence is unclear and could potentially be saying the number five billion is more in some countries and less than others. Five billion is five billion. Additionally, “less” is usually used with non-countable nouns. Lower is used as a comparative with things that have levels (like carbon emissions, the temperature, water). This cannot be the best answer.
Option E: The United States emits over five billion metric tons a year, although it is more than that in some countries and less than that in others.This answer choice uses “less” rather than “lower,” and the “it” doesn’t have a clear antecedent, which causes the same problems as we saw in Options C and D. This cannot be the best answer.
We have successfully eliminated four answer choices. Option A is the best answer. _________________
EMPOWERgmat
Total GMAT Content & Tactical Training | 120 Point Guarantee | All 6 Official GMAT Tests
empowergmat.com