Some kinds of quakes are much more likely to cause tsunamis than other

VERITAS PREP OFFICIAL SOLUTION:

This question is primarily testing sentence construction, but you should start by analyzing the obvious comparison decision point (“compared to” vs. “than”) at the start of each answer. Since the comparison in the sentence starts with “much more likely” it must be followed by “than” – “compared to” is both redundant and unidiomatic. This allows you to confidently eliminate (B) and (C).

For the remaining answers, you need to figure out which one properly links the second part of the sentence with the first – you have the choice between “than others, the” in (A), “than others,” in (D), or “than others;” in (E). To see which is correct, simplify the sentence with slash-and-burn and read the core elements only. For (A) and (D) you have “Some quakes are more likely to cause tsunamis than others, [the] so called megathrust earthquakes are especially likely to generate waves…” This sentence has all kinds of problems! First it is linking together two independent clauses with a comma – a distinct comma splice error that also confusingly makes it seem that “[the] so called megathrust earthquakes” is modifying “others,” That makes no sense, however, as the “others” would be the ones that DON’T cause waves.

(E) correctly uses a semi-colon to link together two related, but independent clauses: “Some quakes are more likely to cause tsunamis than others; so called megathrust earthquakes are especially likely to generate waves…”