The question asks for code blocks that return a 4-partition DataFrame from an 8-partition DataFrame without inducing a shuffle. Coalesce (option C) is designed to reduce partitions by merging existing ones without shuffling, making it the correct choice. Repartition (options A, B, D) always triggers a shuffle, even when reducing partitions, which does not meet the requirement of avoiding a shuffle. Option E is invalid because it lacks the necessary partition count argument. Therefore, the only correct option is C.