from clue 3 and 4 -> 1 number can be 7 OR 3 (since 9 is not correct). Now if 7 was correct and placed in proper spot, it conflicts with Clue 1, thus 7 can’t be the correct number and the correct number is 3 and placed at proper spot (which is 3rd spot).

Now from 2nd clue -> two numbers are correct, one is 3 and other one should be 1 (as we know 7 can’t be correct number), since 1 is placed at wrong spot, correct spot for 1 should be first (since 3rd spot is for 3).

Again from Clue 1: 1 number is correct and placed at wrong spot. we are looking for a number at 2nd spot, it should be 5 (as 7 is not in picture and it can’t be 2 since it is placed at 2nd spot), 5 is placed at wrong spot, its correct spot should be 2nd, since we already know 1st and 3rd spot numbers.

Thus the PIN is 153.