The following 3-year-olds are asked to count the number building blocks (five each) placed in front of them. Which of the following responses best illustrates the one-to-one principle?A. Howie, who says, "1, 4, 2!" B. Heidi, who says, "5, 3, 1, blastoff!"
C. Tyra, who says, "One hand has five fingers."
D. Simon, who says, "1, 2, C, D, F."

The response that best illustrates the one-to-one principle is:

D. Simon, who says, "1, 2, C, D, F."

Explanation:

The one-to-one principle focuses on the importance of attributing only one counting tag to each counted object. The counting tag can be a number, or a letter, for instance. Simply put, the child should not repeat counting tags, such as in "2, 3, 3". They should be able to associate one counting tag to one of the objects. Also, they need to be able to coordinate partitioning and tagging. That means the child must be able to differentiate the objects that have been counted from those that haven't. Notice that, among the responses, Simon offered the one that showed this principle. He was the only one who not only counted all the five objects in the array, but who also assigned only one tag to each object. The fact that he mixed numbers and letters does not affect this principle.

"choosing is refusing" means individuals face an opportunity cost with each decision they make. economists state that every decision involves trade-offs. opportunity cost is the least desirable alternative given up as a result of a decision.