When conducting an experiment on time management, Jamie assigns everyone who arrives before noon to the experimental group and everyone who arrives after 12 noon to the control group. In the context of experimental research methods, what is wrong with Jamie’s experiment?
a) the experiment is deceptive
b) jamie has introduced a confederate into the experiment
c) jamie has not used true random assignment
d) the experiement is not ethical

Random assignment: In scientific or psychological research, random assignment is also referred to as random placement and is described as an experimental phenomenon or technique to assign participant's or subject's including human beings or animals, etc to distinct groups in a research or an experiment, for example, either in control group or in treatment group via the utilization of randomization i.e, through a chance procedure (random number generator).

In the question above, while conducting the experimental research method Jamie hasn't used true random assignment.