Thanks for the question! We’re told here that in older commercial airplanes, control panel design lets changes in flight controls that one person makes be viewed by other crew members. But in newer ones, it’s harder to see these changes, which makes it harder to do cross-checks. So fllight crews have to inform each other verbally more frequently.
So now we’re asked for something that’s most strongly supported by these statements. (E) tells us that the frequency of verbal sharing depends in part on what other means for performing cross-checks are available. Well, the stimulus tells us that less cross-checks otherwise are available, so now there has to be more verbal cross-checking. That directly supports (E), making it correct.
(A) is wrong because the stimulus doesn’t talk about how long the changes take.
(B) is wrong because the stimulus doesn’t say anything about “the most valuable” means.
(C) is wrong because it’s too far to say that there was no need for verbal exchanges back in the old days. Indeed, we’re told that the verbal cross-checks are “more frequent[],” implying that they used to be done too.
(D) is wrong because we’re told that the changes are harder to see, not impossible to see.
Hope this helps! Feel free to ask any other questions that you might have.