This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Social & Preventive Medicine
A cardiologist wants to study the effect of an antihypertensive drug. He notes down the initial systolic blood pressure (mmHg) of 50 patients and then administers the drug on them. After a week's tretment, he measures the systolic blood pressure again. Which of the following is the most aproprate statistical test of significance to test the statistical significance of the change in blood pressure - 
Select and explain. 
A. Paired t-test, B. Unpaired or independent t-test, C. Analysis of variance, D. Chi-square test
A: Paired t-test
Answer: A: Paired t-test 
Explanation: In the given question, a cardiologist wants to study the effect of an anti-hypertensive drug. So he will compare mean BP of 50 patients before and after administering the drug. Thus Paired t-test will be most appropriate test of significance