A recent study confirms that nutritious breakfasts make workers more productive. For one month, workers at Plant A re...

Victoria on May 22, 2021

Hi @Olivia-Cohen,

Happy to help!

The author concludes that a recent study demonstrates that nutritious breakfasts increase worker productivity.

Why? Workers at Plant A received nutritious breakfasts every day before work for one month and their productivity increased. Comparatively, workers at Plant B did not receive nutritious breakfasts and their productivity did not increase.

Answer choice (B) is incorrect because it does not strengthen the conclusion that nutritious breakfasts increase worker productivity. While it could possibly help to eliminate influencing factors in the study, we are focused on comparing the workers' productivity to their own productivity the month prior. In this way, we are not focused on comparing Worker X at Plant A to Worker Y at Plant B. Rather, we are focused on comparing Worker X's productivity to their own productivity a month prior and the same for Worker Y.

Hope this helps! Please let us know if you have any further questions.