OE


Recalcitrant, degradation. The puzzle sounds quite complicated—delivering an antisense strand to the right place at just the right moment. Only recalcitrant (stubborn) is appropriate to describe a complicated puzzle; pedestrian (commonplace, uninspired) conflicts with the clue and monolithic (inflexible, unchanging) is not indicated by any clue. The strand must be strong enough to resist rapid (something), “allowing it time to accomplish its task.” The clue is that the strand needs time to work, so it needs to resist something like “not being able to work.” Dessication (drying out) is probably bad, but there is no indication in the sentence that drying out would prevent the strand from working, and compunction (uneasiness due to guilt) doesn't apply to strands. However, degradation (deterioration; breakdown) is something the strand would have to resist in order to work on the virus.