A team of researchers is testing the effectiveness of a new HPV vaccine. They randomly divide the subjects into two groups.
Group 1 receives new HPV vaccine, and Group 2 receives a placebo.
The patients in the study do not know which group they are in.

a) Which is the treatment group, control group (if there is one)?

b) Is this study blind, double blind, or neither?

c)Is this research Controlled Experiment or Survey?