According to the graph, at what maternal age is the incidence of Down syndrome equal to five times the incidence at age 40?
A)about 29 or 30
B)about 35 or 36
C)about 44 or 45
D)about 46 or 47

Question

According to the graph, at what maternal age is the incidence of Down syndrome equal to five times the incidence at age 40? 
A)about 29 or 30 
B)about 35 or 36 
C)about 44 or 45 
D)about 46 or 47

Quizplus · Accepted Answer

From the graph, we can see that the incidence of Down syndrome at age 40 is about 4 per 1000 births. To find the maternal age at which the incidence is five times this value, we need to look for the point where the incidence curve crosses the value of 20 per 1000 births. This occurs at around 44 or 45 years old. Therefore, choice C is the best answer.

According to the Graph, at What Maternal Age Is the Incidence