<p>I'm pretty sure it's D. We can use process of elimination to come to that. C, "due to," sounds perfectly right as it is, as well as A and B (you were right). I think D is wrong because of parallelism, shouldn't it be "By the time the bank guard closed the doors, a riot had erupted due to the long lines and the shorage of tellers?</p>
<p>I could be wrong though.</p>
<p>And to answer your last question, I haven't taken the SATs yet so I don't know how frequent this type of question appears on the SAT.</p>
<p>yes, the answer is C. It should be corrected as: as a result of. But how is this different from due to and how often is this trickly little devil going to show up on the SAT?</p>
<p>"Due to" isn't exactly the same as "because of." "Because of" would be better in this case, because it implies that the lines and the shortage of tellers are the CAUSE of the riots, not just an EXPLANATION for the riots. Kind of subtle... I would've said there was nothing really wrong with the sentence, but I guess I would've been wrong.</p>