"Crack" is a form of

What young adult behavior would have the least positive impact on one's cognitive reserve in adulthood?

a. Being a marathon runner b. Obtaining a PhD c. Being very active in social organizations d. Cutting back on using one's mental skills to solve nonessential problems

You give your friend instructions about what to buy for a party by quickly rattling off fifteen unrelated grocery store items. Then to check whether your friend got all the information, you ask him to repeat the grocery list back to you. You should expect that your friend will recall about ____ items.?

a. ?two b. ?fifteen c. ?four d. ?seven