A researcher introduces a new mathematics program in one school district and uses a neighboring district as a no-treatment control group. After the program is in place for 6 months, the researcher intends to give the students in both districts a standardized mathematics test and then compare their scores. This research cannot be classified as a true experiment because
the researcher does not control the assignment of participants to groups and therefore has a nonequivalent groups design.

The researcher does not control the assignment of participants to groups and therefore has a nonequivalent groups design.

Explanation: The research design described above is a Quasiexperimental research, which is very similar to an experimental research with one very noticeable difference. In a quasi experimental research, such as described above, groups employed are usually preexisting, meaning that the experimenter does not control or have any impact on assigning subjects into the different groups, The group design are used just as they have preexisted, The nonequivalence portrayed in the group design of quasi experiment usually result in low internal validity expected of an experimental research.

it´s related to his charming character.

beauty is not everything, although we can joke that girls only care about the physical or material aspect, the truth is that a real woman looks at more important things, besides intelligence and personality, there are other attitudes that make irresistible to men who are 'unattractive'.

for example develop your sense of humor.

c- companies fail to take environmental protection into account. i think