Randomization in a clinical trial is done mainly to:
|A||Help ensure the studies subjective are representative of general population|
|B||Reduce selection bias in allocation of treatment|
|C||Ensure group are comparable on base line characteristic|
|D||Facilitate double binding|
Randomization is a statistical procedure by which the participants are allocated into groups.
It is an attempts to eliminate 'bias' and allow for comparability (however, this is never a guarantee as even after randomization the study and control groups may not be comparable on all baseline characteristics, hence the effect of confounding may not be eliminated even after randomly allocating the study and control groups).
It ensures that the investigator has no control over allocation of participants to either study or control group, thus eliminating what is known as selection bias.
Randomization is the "heart" of a control trial.
In this question, however, option A is also equally correct but we go with B. as the answer as it uses the word selection bias.