Which of the following is the kind of decision that can be made at the margin?
a. whether or not to add an extra room to a home.
b. whether or not to hire new workers.
c. whether or not to go on a vacation.
d. whether to have a dog or a cat as a pet.?

B

Explanation:

Nearly all the decisions that doesn't result in true or falls are marginal decisions. For example turning on a light or not is not a marginal decision because it only results in true or false. whereas choosing how many lights to turn on is a marginal decision because we can choose number of lights that needs to be turned on.

That is why hiring new workers is marginal decision. Because we can choose between 1 or more employee to hire.