A: teen pregnancy. You have just as much of a chance getting an STD at any time in your sex life and you're only less likely to finish school if you become pregnant or get your spouse pregnant. Even then that doesn't mean you won't finish high school.
Answer: ruling out rival hypothesis
Explanation:
To rule out rival hypothesis suggests that to exclude the possible explanation for a specific claim. This suggests that before confirming or believing something one has to ensure that other explanation for a specific claim has been disproved to become sure for a specific claim.
According to the given situation, the stress and illness relationship is required to be derived. The increased level of stress and illness is responsible for the decrease in immunity is ruled out by the fact that people due to stress indulge or engage in health damaging behaviors. This is responsible for illness.
If you monitor your practice run you can see how much your improved time wise.