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.

How many persons are lighter than S?

The correct option is Two.

Let us analyze the given information step-by-step to arrange the six persons in descending order of their weights from left to right (from heaviest to lightest):

Let the six positions be represented as:
Position 1 (Heaviest) > Position 2 > Position 3 > Position 4 > Position 5 > Position 6 (Lightest)

Step 1: Placement of Q and T
We are told that "Only T is lighter than Q". This means that T is the lightest person (Position 6) and Q is the second lightest person (Position 5).
We are also given that the weight of Q is 17 kg.

$Weight\; of\; Q\; =\; 17\; kg$

Step 2: Calculate the weights of S and N
"S is twice heavier than Q" means:

$Weight\; of\; S\; =\; 2\; \times \; 17\; =\; 34\; kg$

S is also "14 kg lighter than N", which means:

$Weight\; of\; N\; =\; 34\; +\; 14\; =\; 48\; kg$

Step 3: Determine the positions of S and M
There are "Two persons between M and S". Since Q and T are already fixed at positions 5 and 6, let's look at the possible positions for S:
- If S is at Position 1, N (48 kg) cannot be heavier than S (34 kg) because there would be no position to the left of S. So S cannot be at Position 1.
- If S is at Position 2 or 3, M would have to be at Position 5 or 6, which are already occupied by Q and T. Thus, this is not possible.
- Therefore, S must be at Position 4. With two persons between M and S, M must be placed at Position 1.

So far, the arrangement is:
M (Position 1) > [Empty] (Position 2) > [Empty] (Position 3) > S (Position 4) > Q (Position 5) > T (Position 6)

Step 4: Place N and R in the remaining positions
The remaining positions are 2 and 3, and the remaining people to place are N and R.
We are told that "R is not the second heaviest among all." This means R cannot occupy Position 2.
Therefore, R must occupy Position 3, and N must occupy Position 2.

The final weight-based descending order is:
M > N (48 kg) > R > S (34 kg) > Q (17 kg) > T

Conclusion:
S is at Position 4. The persons lighter than S (to the right of S) are Q and T. Thus, there are exactly two persons lighter than S.