Answer :
The section of the passage which builds tension by speeding up the pace is "All was ready. The signal was given." (option A)
Pace in literature
Authors can make the pace at which a story is told faster or slower depending on the type of sentences they use. As we can see in the passage, short, direct sentences quicken the pace.
"All was ready. The signal was given" are short and direct sentences that make the pace of the story faster, giving the impression that the actions follow each other quickly.
With the information above in mind, we can choose letter A as the best option.
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