The letters L, M, N, O, P, Q, R, S and T in their order are substituted by nine integers 1 to 9 but not in that order. 4 is assigned to P. The difference between P and T is 5. The difference between N and T is 3. What is the integer assigned to N?

Let's think of this as a simple walk on a number line that goes from 1 to 9.\n\n1. **Start at P:** The question tells us P is sitting at number **4**.\n\n2. **Find T:** T is at a distance of 5 from P. \n - If we go forward 5 steps: 4 + 5 = 9. (This is allowed, it's inside 1-9).\n - If we go backward 5 steps: 4 - 5 = -1. (This is NOT allowed).\n - So, **T must be 9**.\n\n3. **Find N:** Now we are standing at T (which is 9). N is at a distance of 3 from T.\n - If we go forward 3 steps: 9 + 3 = 12. (This is outside our 1-9 limit).\n - If we go backward 3 steps: 9 - 3 = 6. (This is inside allowed).\n - So, **N must be 6**.\n\nChecking options: Option (D) matches our intuitive finding.