We have to select 3 digits from 0, 1, 2, 3, 4, 6, 7, & 8.
Analysing first two statements, digit 6 is ruled out. Then statement at No. 5, rules out digits 7, 3 & 8.
Since 6 & 8 are ruled out, according to statement 1, Digit 2 is one of the correct digits and is at the correct place.
According to the third statement, two numbers are correct but wrongly placed. Since number 6 is already ruled out, remaining numbers are 2 & 0. That means 0 comes in first place and 2 is already in the third place. Now we have to choose one number from out of 1, 3 & 4 which will be placed at No. 2 position. Since it is stated in the second statement that out of 6, 1 & 4, one number is correct but wrongly placed and since it is proved that No. 2 occupies the third position, only number remains is 4 and it must at number two position, the answer we arrive at is 042.