An animal study is being conducted to determine the effect of vitamin C on the incidence of common cold. The researcher gives one group of rats the vitamin C pills and the other group of rats gets the ""dummy"" pill (placebo). The rats that received the placebo would be called the group.

Placebo EffectExplanation:Control group is Right Answer.An animal study is being conducted to determine the effect of vitamin C on the incidence of common cold. The researcher gives one group of rats the vitamin C pills and the other group of rats gets the ""dummy"" pill (placebo). The rats that received the placebo would be called the control group.Endogenous opioids, for example, endorphins and enkephalins, are normal pain alleviating synthetic substances created in the body. Absense of pain because of the misleading impact is reliant upon the actuation of propositions endogenous opioids in the brain.

Hydrogen and oxygen