Question

question 6 of 10
which option is an example of an experiment?

a. having customers fill out a questionnaire about their favorite brand of toothpaste

b. finding the number of red jellybeans in an average jar of jellybeans by counting

c. counting the number of times a number cube rolls a 5 out of 30 tries

d. testing the effectiveness of a mouthwash by allowing one group to use it and comparing the results with those of a group that doesn’t use it

Explanation:

• Option A is a survey (collecting data via questionnaire), not an experiment.
• Option B is a counting/observation task, not an experiment.
• Option C is a probability - related activity (counting outcomes of a random process), not an experiment.
• Option D involves manipulating an independent variable (using mouthwash or not) and comparing groups (experimental and control), which fits the definition of an experiment.

Answer:

D. Testing the effectiveness of a mouthwash by allowing one group to use it and comparing the results with those of a group that doesn't use it