Single-case experiments were developed from a need to determine whether an experimental manipulation has an effect on a single research participant. measure only a single dependent variable. overcome selection differences that occur in nonequivalent control group design. have a design that examines a measurement at only one point in time.

determine whether a manipulation has an effect on a single research participant.

Explanation:

d.

thist title points out that you are explaining the nature of the u.s. government. it is the most specific. a representative government consists of a government where decisions are taken according to a voting system. the most essential aspect of a representative government is found in the different structures where voting rights are granted to different groups of people. for example, voting for governor, mayor, president, local police chief etc.