Step 1: Understand the question.
We must find the correct composition of a Disciplinary Committee of a Bar Council under Section 9(1) of the Advocates Act, 1961.
Step 2: Why this committee exists.
The Disciplinary Committee hears cases of professional misconduct against advocates. Its make-up is fixed by statute to keep it fair and balanced.
Step 3: Recall the number of members.
Section 9(1) says each Disciplinary Committee consists of three members. So any option with five members is wrong straightaway.
Step 4: Recall how the three are chosen.
Two members are elected by the Bar Council from among its own members. The third member is co-opted by the Council from among advocates who have the prescribed qualifications and who are NOT members of the Council.
Step 5: Match with the options.
Option B says three members, two elected from the Council and one co-opted advocate with prescribed qualifications who is not a member of the Council. That is an exact match.
Step 6: Eliminate the wrong options.
Option A (five, all co-opted) and Option C (five, three elected plus two co-opted) both have five members, so they fail on number. Option D (three, all elected, junior as Chairman) is wrong because one member must be co-opted, not all elected.
Step 7: Final answer.
\[ \boxed{\text{Three members - two elected from the Council's membership and one co-opted advocate possessing the prescribed qualifications, who is not a member of the Council.}} \]