Consider the following statements in respect of the sum S = x + y + z, where x, y and z are distinct prime numbers each less than 10: 1. The unit digit of S can be 0. 2. The unit digit of S can be 9. 3. The unit digit of S can be 5. Which of the statements given above are correct?
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Correct answer: A. 1 and 2 only
The unit digit of the sum S can be 0 or 9 when summing distinct primes less than 10, but it cannot be 5.
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