Today’s ACT question of the day is an English question designed to prove me right when I say that verbs are the most frequently tested subject on the ACT English section (as well as on the SAT writing section).
The passage about Mickey Mantle is written in past tense and, indeed, the very sentence we are asked to fix is in the past tense (“…when glints of the afternoon sun shone…”). We need to put “there will have to be seen for one brief, stirring moment the glimmer of jewels…” into a tense that is compatible with the past tense.
If we didn’t have “be seen” to content with, we could consider something like “had been seen” or “was seen”, but instead we have to look to the conditional “could” to help us out. “Could” tells us that this situation was possible, but not necessarily common – this fits with the tone of the sentence, too. D is our answer today.