A scientist is conducting a study on the effect of eating chocolate and overall mood. They believe that gender is a significant factor. The participants are divided by gender. Then, within each group, participants are randomly assigned to consume either chocolate or a placebo and then rate their mood for the day. This experiment will run for two weeks. Which type of experimental design does this situation describe

Randomized Block Design

Explanation:

A randomized block design may be defined as an experimental design where  samples or subjects of the experiment are spited into two or more groups called as blocks of the experimental units. Here the variation in each of the block is lower than the variation which is among or between the blocks, such that the variation can be controlled. In the random order, treatments are to be performed on each of the experimental of these blocks.

In the context, the experimental units are divided or grouped by gender and the treatment (of consumption of a chocolate or a placebo) is then randomly administered to the experimental units.

i'd have to with d.

explanation:

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