In a Clinical Trial, 780 Participants Suffering from High Blood

In a clinical trial, 780 participants suffering from high blood pressure were randomly assigned to one of three groups.Over a one-month period, the first group received a low
Dosage of an experimental drug, the second group received a high dosage of the drug, and the
Third group received a placebo.The diastolic blood pressure of each participant was
Measured at the beginning and at the end of the period and the change in blood pressure was
Recorded.Identify the levels of the factor.

A) Placebo, low dosage, high dosage
B) Diastolic blood pressure at the start, diastolic blood pressure at the end
C) The experimental drug
D) High blood pressure, low blood pressure
E) The one-month period