Ruben Has a New Puppy and Wants to Feed It

Ruben has a new puppy and wants to feed it the best possible food. He decides on an experiment where he will feed it the very best canned food plus a dietary supplement of vitamins recommended by a veterinarian. Which of the following best describes Rubenʹs project?

A) Ruben needs to use his motherʹs 6-year-old chocolate shar-pei to feed a standard diet so he can compare his puppy with a control dog.
B) Ruben needs to control for the amount of exercise, sunshine, water, and care that the puppy gets each week, so that they are equal from week to week.
C) Ruben needs to take careful measurements of the puppyʹs weight and height at least once a week for it to be a good experiment.
D) This is not an experimentthere are no controls or replicates.
E) This is an example of an excellent, controlled experiment as it is written.