Study the following information carefully and answer the questions given below-

Six persons are arranged in descending order according to their weight from left to right. Only T is lighter than Q whose weight is 17kg. S is twice heavier than Q and 14 kg lighter than N. Two persons between M and S. R is not the second heaviest among all.

Who is the heaviest among all?

The correct answer is M.

Let us break down the clues step-by-step to determine the order of the six persons from heaviest to lightest (descending order from left to right):

Step 1: Position of Q and T
The clue states: "Only T is lighter than Q."
This means Q is the second lightest person, and T is the lightest person. Placing them in the 5th and 6th positions respectively, we get:
1 (Heaviest) > 2 > 3 > 4 > Q > T (Lightest)
We are also given that the weight of Q is 17 kg.

Step 2: Calculate the weights of S and N
We are told: "S is twice heavier than Q and 14 kg lighter than N."
Using the weight of Q (17 kg), we can calculate the weight of S:
$\text{Weight of}S=2\times 17\text{kg}=34\text{kg}$
Since S is 14 kg lighter than N, the weight of N is:
$\text{Weight of}N=34\text{kg}+14\text{kg}=48\text{kg}$
Since N (48 kg) is heavier than S (34 kg), N must be positioned to the left of S in the descending order.

Step 3: Position of M and S
The clue states: "Two persons between M and S."
Since Q and T occupy positions 5 and 6, S can only be placed in position 4. If S were in any other position, we could not satisfy the spacing or weight constraints (for example, if S were in position 3, M would have to be in position 6, which is already occupied by T).
With S in position 4, M must be in position 1 (as there are two positions, 2 and 3, between 1 and 4):
1 (M) > 2 > 3 > 4 (S) > 5 (Q) > 6 (T)

Step 4: Position of N and R
The remaining positions to fill are 2 and 3, and the remaining persons are N and R.
The clue states: "R is not the second heaviest among all."
Therefore, R cannot be in position 2. This means R must be in position 3, and N must be in position 2.
This gives us the final arrangement:
1 (M) > 2 (N) > 3 (R) > 4 (S) > 5 (Q) > 6 (T)

Comparing their weights:
- Weight of N = 48 kg
- Weight of S = 34 kg
Since R is between N and S, R's weight lies between 48 kg and 34 kg, and M (position 1) is the heaviest with a weight greater than N (48 kg).

Thus, M is the heaviest among all.