Context: Austen and his classmates are growing tomato plants in the school garden. He wonders what factors affect how tomato plants grow. So, he decides to design an experiment. He has the following supplies available:
three different types of tomato seeds
one bag of potting soil
five identical clay pots
water
Using only these supplies, which question can Austen investigate with an experiment?
A. Which of the three types of tomato seeds sprouts the fastest?
B. Does a certain kind of tomato plant grow taller when planted in a clay pot or in a plastic pot?
C. Which type of soil will cause a certain kind of tomato plant to grow the most fruit?
From the given choices, select the correct answer and reply with the letter of the chosen option.

A