
Passage: Since the cancellation of compulsory premarital check-ups in city B in 2003, the city's premarital check-up rate has fallen from nearly 100% 10 years ago to 7% in 2011, and it is the lowest in the country. At the same time, the incidence of birth defects in the city has doubled. Thus it can be seen that the abolition of the compulsory premarital examination system has led to an increase in the rate of birth defects.
Question: Which of the following options is not relevant to the evaluation of the above argument?
A. A.Has the city's living environment (air and water quality, etc.) been damaged in the past decade?
B. B.Has there been a substantial increase in unhealthy lifestyles such as staying up late and surfing the Internet for a long time among people of childbearing age in the city in the past decade?
C. C.Have women in the city delayed giving birth in the past decade, and has the proportion of elderly pregnant women increased greatly?
D. D.Has the number of floating population in the city increased or decreased in the past ten years?
Answer: