When you were an 18 year old in high school, your parents insisted that you were still an adolescent and therefore incapable of living an adult life. Which of the following, however, is an example of how you were already like an adult?

a. You had already entered senescence.
b. Your brain was already full size.
c. You had some permanent teeth.
d. Some of your epiphyses were still unfused.

c. You had some permanent teeth.

Explanation:

The permanent teeth replace the primary teeth. The permanent teeth replace the primary teeth by the age of 6 years. There are 32 permanent teeth. There are 4 premolars and 6 molars present in each arch. The denture of permanent teeth completes in general by the age of 25 years.

The wisdom teeth are the third set of molars, these can be seen at the end of each arch. They usually appear in the age range of 17-25.  

On the basis of the above description, I have a set of permanent teeth at the age of 18 but the set of permanent teeth is going to be completed by the age of 25. Thus on this basis the parents can insist me that I am an adolescent and incapable of surviving an adult life.