You are a helpful assistant. When the user asks a question, your response must include two parts: first, the reasoning process enclosed in <think>...</think> tags, then the final answer enclosed in <answer>...</answer> tags.Please provide a clear, concise response within <answer> </answer> tags that directly addresses the question.
system
<image>In order to study the relationship between drinking alcohol and hypertension, a case-control study was conducted in 1992 by the Epidemiology Department of Shandong Medical University on the basis of community-based population screening, in which 154 new cases of hypertension were randomly selected as a case group and 583 normal people as a control group. The past alcohol consumption of the study subjects was investigated, along with variables such as age, sex, and body mass index (BMI>24 as overweight). Considering that body mass index may be a potential confounder when analysing the relationship between drinking alcohol and hypertension, it needs to be analysed and judged. The following table presents unstratified information on the relationship between the drinking alcohol and hypertensive disorders. <image 1> The cOR between the drinking alcohol and hypertensive is
A. 1.70
B. 2.50
C. 3.20
D. 4.80

Please answer the question with option letter from given choices in the format of Answer: <option letter>. You FIRST think about the reasoning process as an internal monologue and then provide the final answer. The reasoning process MUST BE enclosed within <think> </think> tags. Please answer the final answer within the <answer> </answer> tags.
user
A
In order to study the relationship between drinking alcohol and hypertension, a case-control study was conducted in 1992 by the Epidemiology Department of Shandong Medical University on the basis of community-based population screening, in which 154 new cases of hypertension were randomly selected as a case group and 583 normal people as a control group. The past alcohol consumption of the study subjects was investigated, along with variables such as age, sex, and body mass index (BMI>24 as overweight). Considering that body mass index may be a potential confounder when analysing the relationship between drinking alcohol and hypertension, it needs to be analysed and judged. The following table presents unstratified information on the relationship between the drinking alcohol and hypertensive disorders. <image 1> The cOR between the drinking alcohol and hypertensive is
A. 1.70
B. 2.50
C. 3.20
D. 4.80

Please answer the question with option letter from given choices in the format of Answer: <option letter>. You FIRST think about the reasoning process as an internal monologue and then provide the final answer. The reasoning process MUST BE enclosed within <think> </think> tags. Please answer the final answer within the <answer> </answer> tags.
val