Answer:
Step-by-step explanation:
Hello!
A confounding variable is any variable that may affect the response variable other than the explanatory variable defined by de investigator.
For this example, the objective is to test if drinking something sweet once or twice a day doubles the risk of being seriously overweight one year later.
The explanatory variable is X: Number of sweet drinks a 3- 4- year old kid has a day (one or two)
The response variable Y: Risk of having overweight of a 3- 4- year old kid
Any other variable that modifies the risk of having overweight.
For example:
X: Weekly amount of exercise.
X: Diet of the kid (Fast Food, Sweets, balanced diet)
X: History of obesity in the family of the child.
X: Health status of the child.
I hope it helps!