Which condition is NOT likely to result from exposure to indoor formaldehyde pollution? 

A)  ulcers 
B)  headaches 
C)  dizziness 
D)  chronic breathing problems

What is the age structure of a population? 

A)  It is the number or percentage of males that are ages 15 to 44. 
B)  It is the number or percentage of females that are age 14 or under. 
C)  It is the number or percentage of persons of each sex at each age level. 
D)  It is the number or percentage of females that are ages 15 to 44.