Eight persons L, M, N, O, P, Q, R and S work on different designations in a company i.e., MD, COO, CEO, CFO, CTO, CMO, Manager and HR. The order of seniority is same as given i.e., MD is the senior-most designation and HR is the junior-most designation.

Three persons are there between S and L. L works below CMO. N is junior to MD but senior to S. More than three persons work between N and P. Same number of persons are junior to P and senior to M respectively. R is senior to CMO but junior to Q.

O works on which among the following designation?

The correct answer is CMO.

Step-by-step Explanation:

First, let us list the designations in order of decreasing seniority (from senior-most to junior-most):

1. MD (Senior-most)
2. COO
3. CEO
4. CFO
5. CTO
6. CMO
7. Manager
8. HR (Junior-most)

Now, let us analyze the given clues step-by-step to place each person in their respective designation:

1. Analyze L and S:
- Clue: "L works below CMO." Therefore, L can be either Manager (position 7) or HR (position 8).
- Clue: "Three persons are there between S and L."
• If L is at position 8 (HR), then S must be 3 spots above, which is position 4 (CFO).
• If L is at position 7 (Manager), then S must be position 3 (CEO).

2. Analyze N and P:
- Clue: "N is junior to MD but senior to S." Since N is senior to S, S cannot be at position 3 (CEO), because N must be between MD (1) and S. If S were at position 3, N would have to be at position 2 (COO). But let us check the other condition.
- Clue: "More than three persons work between N and P." This means there must be at least 4 persons between N and P.
• Let us test Case 1: L = HR (8), S = CFO (4).
Since N is junior to MD (1) and senior to S (4), N can be at position 2 (COO) or 3 (CEO).
If N is at position 2 (COO), to have more than 3 persons (at least 4 persons) between N and P, P must be at position 7 (Manager) or 8 (HR). Since L is at 8, P would be at 7 (Manager).
Let's verify the number of persons between N (2) and P (7): positions 3, 4, 5, 6 are between them, which is exactly 4 persons (more than 3). This is valid!

3. Analyze M:
- Clue: "Same number of persons are junior to P and senior to M respectively."
P is at position 7 (Manager), so there is 1 person junior to P (HR at position 8).
Therefore, there must be 1 person senior to M, which means M is at position 2 (COO).
Since M is at position 2 (COO), N must be at position 3 (CEO).

4. Analyze Q and R:
- Clue: "R is senior to CMO but junior to Q."
The remaining available positions senior to CMO (positions 1 to 5) are position 1 (MD) and position 5 (CTO).
Since R is junior to Q, Q must be at position 1 (MD) and R must be at position 5 (CTO).

5. Determine O's designation:
- Placing the remaining person, O, in the only unassigned designation, which is position 6 (CMO).

Final Arrangement:
1. MD: Q
2. COO: M
3. CEO: N
4. CFO: S
5. CTO: R
6. CMO: O
7. Manager: P
8. HR: L

Hence, O works as the CMO.