An Equivalent Time-Series Design Is ___________________

An equivalent time-series design is ___________________.

A) an effect of two independent variables operating simultaneously and in combination on a dependent variable. It is a larger effect than occurs from the sum of each independent variable working separately
B) experimental designs that lack random assignment or use shortcuts and are much weaker than the classical experimental design. They can be substituted in situations in which an experimenter cannot use all the features of a classical experimental design, but have weaker internal validity
C) an experimental design in which there are several repeated pretests, posttest, and treatments for one group, often over a period of time
D) a pre-experimental design that has one group, a pretest, treatment, and a posttest. It lacks a control group and random assignment