Researchers conducted a study to determine the effects of stress on the immune system by measuring immune system chemicals. to accomplish this goal, they compared college students who were undergoing a stressful series of exams to a group of similar students relaxing during a time of no classes and no exams. the results of this study indicate that

The correct answer is, The results of this study indicate that the exam group tested lower for the immune system chemicals.

Explanation:

Immune system is simply the defense mechanism of the body. It is a system of the body which fights for the body against the harmful infections or other invaders. This system has a large network of cells, tissues, and organs which work together to protect the body.

Many factors affect the immune system of the human body. Some main factors are Stress, Anxiety, diseases like AIDS, any viral infections, etc. All such things weaken the immune system. And when immune system weakens, the body defense mechanism also weakens and is not fully ready to fight against the infectious organisms which may attack the body.

So when a study was conducted by testing the chemicals levels of the immune system to find the stress effects on a human body immune system, the researchers found that the students who were stressed due to exams had lower level of immune system chemicals as compared to the students who were relaxed on a normal day at college.