prachich1987 wrote:The relationship between cell phone use and the incidence of brain tumors is still unclear, this is because some studies show a causal relationship while others do not.

A) is still unclear, this is because some studies show
B) is still unclear; some studies show
C) are still unclear because some studies show
D) is still unclear because: some studies show
E) is still unclear; the reason is that some studies show

The OA is B. But I don't understand what's wrong with E.Though it is wordy it maintains the contrast between two sentence while B doesn't...

Idenfication marker - is vs are with single vertical look ( left with ABDE)
Identification marker 2 - redunadancy - A ( repetition of 'this') , the reason is reduandant because the first clause itself makes clear that the relationship is still unclear same goes with option C also because "because' is not required since the first clause itself makes the intent clear.

B is the best choice

Received PM...

Answer choice B does maintain the contrast between the two studies in the sentence. It says, " some studies show a causal relationship while others do not." This is a contrast. In fact, all of the answer choices give this contrast.

What you are looking for at this point is the most effective way of expressing this. If you look at various explanations in the official guide you will find that quite often the correct answer is said to be "brief" or "concise" and the incorrect answer is said to be "wordy" or redundant". Winners Attitude mentions this in the posting above.

My rule of thumb for something like this is that you can choose the longer answer choice if it brings you extra clarity of meaning or makes a more logical choice. However, if exactly the same thing is expressed the briefer choice will be preferred. In this case saying "the reason is that" in choice E is not necessary to the logical or grammatical clarity of the sentence. This is because the "The is because" is already implied!