Greenhouse workers are exposed to unique environmental conditions that include enclosed spaces, high temperature, high humidity and elevated levels of airborne microorganisms. A research study conducted in the month of July found an increased prevalence of respiratory symptoms (cough, wheeze and phlegm) among workers employed in 3 Midwestern greenhouses. This is an example of a .

The correct answer is - a cross-sectional study.

Explanation:

A cross sectional study is a type of study that helps in the analyzing data from a population at particular time. It is helps in to check that if a particular risk exposure will leads to particular result.

In the given case it is the example of the cross sectional study or analysis as it is deals with the effect of the environmental condition to the greenhouse worker to the increased prevalence to respiratory disorder.

Thus, the correct answer is - a cross sectional study.

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b. inhalant--> dissolves fatty tissue in the brain

c. marijuana--> changes how the hippocampus processes sensations