Memory Class

An elderly couple had been experiencing declining memories, so they decided to take a power memory class where one is taught to remember things by association.
A few days after the class, the old man was outside talking with his neighbor about how much the class helped him.
"What was the name of the Instructor?" asked the neighbor.
"Oh, ummmm, let's see," the old man pondered. "You know that flower, you know, the one that smells really nice but has those prickly thorns, what's that flower's name?"
"A rose?" asked the neighbor.
"Yes, that's it," replied the old man. He then turned toward his house and shouted, "Hey, Rose, what's the name of the Instructor we took the memory class from?"