Manny has been unable to sleep for the past one week. his wife gives him a vitamin pill and tells him that it will him sleep at night. the next morning, manny is thrilled because he has slept better than ever before. in this scenario, manny's response to the vitamin can be attributed to

Placebo effect

Explanation: Placebo effect is defined as substances that produces no specific effect .Placebo is a medicinal drug in the field of medicine.This drug has certain effects on certain people on the basis on how they feel after intaking and the nature of illness .

This substance can behave as the fake medicine to generate the real effects .Manny's wife has also given him the vitamin pill which can be in regards with the placebo substance effects.

answer; /// i believe that the correct answer is (a) making presentations;