When two or more medicines are taken at the same time, they can work together in one of three ways: additive, synergistic, or antagonistic interaction.
What is synergistic interaction?

Two drugs can have a synergistic effect if they increase each other's effectiveness when taken together. There are two main types of synergistic drug interactions. Additive synergistic reactions are those in which the combined effects of two or more drugs are equal to the sum of those drugs' individual effects. Enhanced synergy occurs when the combined effect of the drugs is greater than the sum of those drugs' individual effects.

Explanation:

answer; i believe the answer is moderate level;

the psychologist would claim that the research results were significant.