To ensure that all your participants have an equal opportunity to be in either experimental group (one receives a drug, the other group receives a placebo), you decide to toss a coin to determine who gets placed in which group. You have engaged in . a. matching b. random assignment c. selective participation d. random sampling e. random participation

random assignment

Explanation:

Random assignment is an experimental technique that seeks to form random and fully randomized experimental groups in relation to the treatments presented in the research. This type of technique prevents the formation of "combined groups" that show the differences to each other and can generate a comprehensive result on the research, thus the random formation of diverse groups that can represent a much larger and different population.

An example of this can be seen in the question above, where the researcher decides the formation of the group that will receive the medicine and the group that will receive the placebo, completely randomly.