Question

maria wants to determine which type of disinfectant kills the most bacteria. which of the following is the best way for maria to determine this? a. ask ten different companies that make disinfectants which type is best. b. put the same amount and species of bacteria on ten identical plates, and add ten different kinds of disinfectant to each plate. c. put the same amount and species of bacteria on ten identical plates, and add a different disinfectant to each plate. d. interview ten different people to determine which type of disinfectant they prefer.

Explanation:

To determine which disinfectant kills the most bacteria, a controlled experiment is needed. Option A relies on companies' claims, which are biased. Option B uses ten different disinfectants on each plate, which is not a valid experimental design (mixing disinfectants). Option D is about people's preferences, not bacterial kill. Option C sets up a controlled experiment: same bacteria amount/species, identical plates, and a different disinfectant per plate to compare their effectiveness.

Answer:

C. Put the same amount and species of bacteria on ten identical plates, and add a different disinfectant to each plate.