A research study aims to evaluate the effectiveness of a new drug in reducing blood pressure. The study involves 100 participants, who are randomly assigned to two groups: one group receives the new drug, and the other group receives a placebo. Blood pressure measurements are taken at the start of the study and after 12 weeks of treatment. What is the dependent variable in this study? The blood pressure measurements after 12 weeks of treatment The type of drug administered (new drug or placebo) The duration of the study (12 weeks) The number of participants in each group