10. 

Three groups of rats acquire a memory on Day 1. On Day 2, rats in Group 1 are given a drug which prevents initial long-term storage while they are actively retrieving the memory. Rats in Group 2 receive the drug but do not engage in memory retrieval. Rats in Group 3 actively retrieve the memory, and are shocked six hours later when they are not engaged in retrieval. On Day 3, all three groups are assessed. Which will show the greatest impairments in memory?