Which behavior demonstrates an understanding of one-to-one correspondence?

• A. Counting a group of ten objects by touching each object while saying its number aloud
• B. Counting a group of objects while saying different numbers
• C. Pointing at a single object while naming a number
• D. Counting only some of the objects while speaking aloud

Answer: (A)

One-to-one correspondence in counting means every object in a group gets its own unique count word, and each count word refers to exactly one object. Counting by touching each object and saying the next number aloud shows this clearly: you move through the group, giving a new number to each object in order, so every object is counted once and no numbers are skipped or repeated. This is the essential way children demonstrate they understand that objects map one-by-one to numbers as you count.

Other behaviors don't show that complete, orderly pairing. If you count objects while saying different numbers, the sequence isn’t upheld and you can’t reliably match each object to a single number. Simply pointing at one object while naming a number labels that object but doesn’t count the whole group. Counting only some of the objects leaves part of the group uncounted, so there’s no full one-to-one mapping for the entire set.