Answer : 4. "93747"
Explanation :

Answer: D) 93747 Explanation: From the hints, Only two options for 1st and 2nd digits => 4,2 and 9,3 since it is single digits Sum of second and third digit  = 10  If 2 => 3rd digit = 8 If 3 => 3rd digit = 7 4th digit = 2nd digit + 1 => (2+1 =3) or (3+1 = 4) Sum of all digits = 30 Let 5th digit be x => 1st possibility = 4 + 2 + 8 + 3 + x = 30 => x = 13 (Not possible since it has 2 digits) => 2nd possibility = 9 + 3 + 7 + 4 + x = 30 => x = 7 Therefore, the PIN is 93747