Concept:Short-term memory holds a small amount of information for about 20–30 seconds.Explanation:The question asks for the memory type that retains data for 20–30 seconds.Short‑term memory is a temporary storage system with limited capacity.It can typically hold around seven items at a time.Without active rehearsal, this information fades quickly or is lost.This matches the 20–30 second duration given in the question.Answer:B. Short term memory