Hi Ann! This is a Justify the Conclusion question. In a typical Justify question, there will be some sort of gap between the premises and the conclusion. The correct answer choice is
sufficient to leap over that gap and link the premises to the conclusion.
So first, we want to identify the conclusion. For this stimulus, it's the statement, "Computer passwords are not
going to be replaced by these other options anytime soon."
The premises are 1) Experts say that computer passwords are less secure than other options, 2) Other options are more expensive, and 3) Other options will replace passwords only if they become standard on most computers.
(Side note: if we were to write that last premise as a conditional, what would it look like? It would look like this: If other options replace passwords
They have become standard. It would NOT be: If other options become standard
They will replace passwords. Remember that the phrase "only if" always introduces a
necessary condition. This can be a tricky concept for many people, so please review Lesson 2 in the LSAT Course Book if this stuff is giving you trouble!)
Now, do those 3 premises lead us 100% logically to our conclusion that passwords will not be replaced by other options anytime soon? No! There are gaps that we can think of. For example, what if the other options become less expensive and standard very soon? There is nothing in our premises that talks about any change being a long way away. Yet that is precisely what the conclusion deals with. Whenever there is a concept or idea in our conclusion that was not present in the premises, that is a clear
gap between the premises and the conclusion. In other words, the conclusion does not follow logically from the premises because there is a new concept in the conclusion that was not previously accounted for. A correct Justify answer choice is going to close that gap by explaining the new concept, and therefore lead our premises 100% logically to the conclusion. So here, we are looking for an answer choice that closes the gap by telling us how those alternative security options are not going to be cheap and standard in the near future. (D) does just that.
The other answer choices do not. (A) and (B) do not address the gap. (C) does address the idea of "anytime soon", but the whole answer choice is essentially just a re-statement of the conclusion (it does nothing to fix the gap). (E) also does nothing to tell us why the alternative security options are not getting cheaper and more standard anytime soon, which is what we need in order for the conclusion to follow logically from the premises.
Justify questions can be tricky for a lot of test-takers. Some students struggle with finding the gap between the premises and the conclusion, and others get Justify question stems confused with Assumption question stems. Review lessons 4 and 5 in the LSAT Course books if you find yourself having trouble. Hope that helps!