Which method can be used to make a reliable guess that a victim was under 17 years old?
a) look for flat-bladed incisors
b) look for presence or absence of wisdom teeth
c) multiply the internal distance in centimeters between the coronoid processes by the external distance in centimeters between the jaw angles(mandibular angles)
d) look for shovel shaped incisors
(it's not c)

B) look for presence or absence of wisdom teeth

Explanation:

The only way to make a reliable guess if a victim was under 17 years old is by looking if he already had the wisdom teeth, this teeth are located in the back of the mouth, and are the third molars that humans develop after the age of 17 or 18 years on average, some could develop them after.

i think it is true since you can test the answer and can use observations to complete it.