This is not a realistic GMAT question. For one thing, from the stem it appears that you ought to know in advance what a 'refined number' is; the question should make clear in the stem that 'refined numbers' are an invention of the question designer. In any case, the question is really testing Critical Reasoning skills rather than Quant skills - in technical language, it's testing the distinction between necessary and sufficient conditions. If from Statement 1 we know: "Any refined number must be divisible by 22" that does *not* mean "every number which is divisible by 22 is a refined number". To give a more familiar example, if i tell you that every perfect square is non-negative, that doesn't mean that every non-negative number is a perfect square; 2 is not a perfect square, for example.
If Statement 1 is true - that any refined number is divisible by 22 - it might be that there is only one 'refined number' in the world, 22,000 say, and the probability is 0 that we pick a refined number when picking from the numbers between 0 and 1000. Or it might be that every multiple of 22 is a refined number, in which case the probability is greater than zero.
Statement 2 on the other hand tells us that refined numbers are precisely multiples of 22 from which we can find the probability, so the answer is B.
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