In data sufficiency, a test taker is presented with a question followed by two possible solutions, usually a formula or a phrase. The five options are always the same and always appear in the same order. If choice A is incorrect, then choice D is also incorrect. Similarly, if A is correct, then C and E are also automatically wrong. Likewise, in the problem-solving sections, savvy test takers will see impossible solutions.
Most answers have solutions that are greatly diverge of the correct answer.
Other answer choices are the solution of one step of a multi-step problem. Process of elimination also is useful on the sentence correction portion, too. Two of the five often begin with similar groups of words. If the group of words is correct, other answer choices can be eliminated. If the group of words is incorrect, those choices can be thrown out.