Researchers want to test the effects of a new weight loss program. They believe that gender is a significant factor. The participants are divided by gender. Then, within each group, participants are randomly assigned to either the treatment or control group. Which of the following would be the most effective to test the effects of the new weight loss program? a) Alongitudinal observational study
b) A matched-pair design experiment
c) A randomized block design experiment
d) A completely randomized design experiment

C: A randomized block design experiment

Step-by-step explanation:

We are told the participants are divided by gender into groups which we can call blocks. Then, within each group, they are randomly assigned to either the treatment or control group. This means they are assigned treatments within each block.

A randomized block design is defined as an experimental design whereby the experimental units are divided into groups which we call blocks. After that treatments will be randomly assigned to the experimental units within each of the blocks.

Thus, this corresponds with our question and we can say it's a randomized block design experiment.

where are the choices?