Which type of encoding tends to lead to the longest amount of retention?

During middle toddlerhood, more children have received ____ and their _____ stronger, which contributes to a lower death rate

a. vitamin B; lungs are b. calcium; heart is c. immunizations; immune system is d. viral infections; muscles are

Parkinson's disease has been attributed to ____________________________ dopamine in certain areas of the brain

a. an excess of b. insufficient amounts of c. increased turnover of d. the metabolization of