Strings - Programming

Q1:

Which of the following is correct way to convert a String to an int?
  1. String s = '123'; 
    int i;
    i = (int)s;
  2. String s = '123';
    int i;
    i = int.Parse(s);
  3. String s = '123'; 
    int i;
    i = Int32.Parse(s);
  4. String s = '123'; 
    int i;
    i = Convert.ToInt32(s);
  5. String s = '123'; 
    int i;
    i = CInt(s);

A 1, 3, 5

B 2, 4

C 3, 5

D 2, 3, 4

ANS:A - 1, 3, 5

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