1. In an investigation of the effects of reduced glutathione tablets and adefovir dipivoxil and their potential interaction effects in the treatment of abnormal liver function, research subjects were randomly divided into three groups. Group A took adefovir dipivoxil, group B took reduced glutathione tablets, and group C took both reduced glutathione tablets and adefovir dipivoxil at the same time. A transaminase test was performed to measure the effect of treatment, and the results were compared using t-tests.

(a) Is the research design appropriate in this study? If not, please propose your design to improve the research.

(b) How are the principles of control, randomization, and replication reflected in your design?

(c) Which statistical method should be employed in concordance with your design?