Explanation:

Number of candidates who had none of the three = Total number of candidates - number of candidates who had at least one of three devices.

Total number of candidates = 200.

Number of candidates who had at least one of the three = n(A ∪∪ B ∪∪ C)
Where A is the set of those who have a two wheeler,

B is the set of those who have a credit card and C is the set of those who have a mobile phone.

n(A ∪∪ B ∪∪ C) = n(A) + n(B) + n(C) - {n(A ∩∩ B) + n(B ∩∩ C) + n(C ∩∩ A)} + n(A ∩∩ B ∩∩ C)

Therefore, n(A ∪∪ B ∪∪ C) = 100 + 70 + 140 - {40 + 30 + 60} + 10
Or n(A ∪∪ B ∪∪ C) = 190.

As 190 candidates who attended the interview had at least one of the three gadgets, (200 - 190 = 10) candidates had none of three.

Hence, option 3 is the correct answer.