But when shall we be stronger? will it be the next week, or the next year?

what best describes the rhetorical strategy henry uses here? select all that apply.

declarative statement
imperative statement
interrogative statement
rhetorical question

The answer that best describes the rhetorical strategy that Henry uses here is D. rhetorical question. Rhetorical questions are those that do not necessarily demand an answer - the answer is either obvious so it doesn't have to be stated, or there is no reason to say it.
However, if you need more than one option, I'd also choose interrogative statement, given that this strategy involves the use of questions, which fall under the category of interrogative sentences.