How the future will turn out depends upon the stories—

Concept

A passage-completion question is settled by the passage's own wording, not by general plausibility. The method is fixed: find the sentence in the passage that makes the same claim as the stem, then read off the clause that completes it. Distractors in such items usually lift genuine phrases from the passage that are attached to a different claim.

Application

The stem asks what the turning out of the future depends on. The passage states: "And how the future will turn out depends partly, possibly largely, on which stories we collectively choose to believe." The clause that completes that dependence is "we collectively choose to believe in".

Contrast

• "Which are repeatedly narrated" reflects the passage line that which stories are "picked up and repeated" and which are "dropped and forgotten" determines how we progress and which few survive as our history, knowledge and understanding — a claim about progress and survival.

• "Designed to spread fear and tension" reflects "Some stories are designed to spread fear and concern", where the passage is classifying one type of story and the motive of its teller.

• "Designed to make prophecy" has no counterpart in the passage; the forward-looking stories there appear as totemic warnings and as reassurances, that is, as types of story.

Cross-check

The closing sentence of the passage restates the same dependence: "What the future holds for us is which stories we hold on to and how we act on them" — that is, on the stories we accept and carry forward.

Hence the completion is "we collectively choose to believe in".