OFFICIAL EXPLANATION
A major result of poaching is that there are not as much elephants today as there were a hundred years ago.A. A major result of poaching is that there are not as much elephants today as there were a hundred years ago
That's not it.
This answer choice is grammatically incorrect: the article much can describe only non-count nouns whereas the noun elephants is a count noun.
What helps you identify the mistake is the following Stop Sign:
much, (a) little, less, the amount of—the described noun should be non-count
B. Poaching results in there not being as much elephants today as there were a hundred years ago
Incorrect.
This answer choice repeats the original article mistake: the article much can describe only non-count nouns whereas the noun elephants is a count noun.
Furthermore, the use of the phrase in there not being is stylistically awkward.C. A major result of poaching is that there are not as much elephants today as there were a century ago
Incorrect.
This answer choice repeats the original article mistake: the article much can describe only non-count nouns whereas the noun elephants is a count noun.
Note that this answer choice improves the sentence stylistically: replacing the two-word phrase hundred years with the single word century makes this answer choice more concise than the original sentence. However, grammatical correctness is more important than stylistic preferences. The correct answer can be stylistically flawed but it can never be grammatically incorrect.D. A major result of poaching is that there are not as many elephants today as there were a hundred years ago
This answer choice corrects the original article mistake by replacing much with many to describe the count noun elephants.E. Poaching is a major cause for there not being as many elephants today as there were last century
Incorrect.
While this answer choice corrects the original article mistake, it changes the meaning of the original sentence - a hundred years ago and last century are not the same thing.
Furthermore, the phrase for there not being is stylistically awkward.