We want to evaluate dog owners' reactions to a new dog food product formulation that contains more vegetables.

We bring dog into a lab setting-a kennel-like structure where the dogs are in a no-light setting. The bowl of a small amount of food slides through a small slot door into the dog's holding area. Each dog receives two bowls 4 hours apart, one with the greater vegetable content and one with the original content, where the order is randomized. Speed to first bite is measured as well as the time to consume the full food amount. The dogs are removed from the holding area for exercise and play between bowls. The sample contains 12 different breeds and sizes of dogs.

In this dog food experiment, causation explains ___________.

Multiple Choice

a. why we are measuring how quickly they are drawn to eat the food

b. why we are manipulating the formula

c. why the dogs are isolated

d. All the above are correct

e. why we are controlling the dogs' ability to see the food