Step-by-Step Logical Deduction

To determine the membership of Committee C, we must first use the specific condition given in this version of the question to find the size of each committee, and then use the placement rules to assign the remaining individuals.

1. Apply the Specific Condition and Find Committee Sizes

The question provides a specific scenario: "T, S and X are the only individuals serving on Committee B".

• This directly sets the size of Committee B: Size(B) = 3.
• Using the rule "Committee A should consist of exactly one member more than Committee B", we find the size of Committee A:
  Size(A) = Size(B) + 1 = 3 + 1 = 4.
• Since there are 9 individuals in total, we can find the size of Committee C:
  Size(C) = 9 - Size(A) - Size(B) = 9 - 4 - 3 = 2.

2. Identify Remaining Candidates

The members of Committee B are {T, S, X}. The remaining individuals who must serve on either Committee A or Committee C are:

{Z, Y, W, V, U, R}

3. Assign Members to Committees A and C

We now use the placement rules on the remaining 6 individuals to fill the 4 spots on Committee A and 2 spots on Committee C.

• The rule states: "Among Z, Y and X none can serve on Committee A".
• From our pool of remaining candidates {Z, Y, W, V, U, R}, this means Z and Y cannot be on Committee A.
• The pool of candidates for Committee A is therefore {W, V, U, R}. Since Committee A has exactly 4 members, these must be its members.
• So, Committee A = {W, V, U, R}.
• The only individuals left to serve on Committee C are those who were not assigned to A or B.
• The remaining individuals are Z and Y.

We can check this against the rule for Committee C ("Among T, S and R none can serve on Committee C"). Our result, C = {Z, Y}, does not violate this rule.

Conclusion

Given the specific conditions, the membership of Committee C must be Z and Y.