This is a suspect question, because it uses the word 'series', but goes on to list sets or sequences of numbers. The word 'series' has a precise definition in mathematics - one you don't need to know for the GMAT - and the question is nonsensical if one interprets it literally; a series doesn't have a standard deviation at all.
If you replace the word 'series' with 'set', zenithexe's explanation is perfect. Standard deviation is based on the distances between things in the set, while the mean is based on the sizes of things in the set, so Statement 1 is completely irrelevant. Range only takes into account two values - the extremes - while standard deviation takes into account all values, so Statement 2 isn't very useful. For example, you could have the set:
{-500, 500,500,500,500,500,500,500...,500,1500}
with a trillion 500s in the middle. This set has a mean of 500, a range of 2000, and a standard deviation almost equal to zero. Of course, that's essentially what zenithexe said above.
In any case, it's a dodgy question, and if you don't even have the OA, I'm not sure why you're using the source.
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