Source: official paper test 37

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OA is [c]...Here's my reasoning why that shouldn't be the choice: If sunspots can determine the exact same forecast as 'other evidence' then we know that whatever evidence sunspot provided was helpful..This strengthens the conclusion that sunspots aid in forecasts.
However, in [d], since scientists don't know if its going to be a 11-year cycle or not, they really can't use the cycle to predict weather...so this weakens the conclusion...
what am i missing?? any help appreciated!

I think this argument is straight forward.

It is presenting new findings and then concluding that these new findings WILL help in FUTURE weather forecasts.

Ans. C: Is saying that metereologists have been forecasting weather using technique that generates SAME RESULTS as the sunspot activity does. This means that NO NEW RESULTS WILL STEM OUT of this new technique. No new results, goes against the conclusion which implies improvements in forecasting.

Hope this helps.

As far as answer D:

Who cares about what causes the pattern, the argument presents a FACT that there is this 11-year cycle which creates a weather pattern, so leave it at that. The argument is concerned with whether the new findings will help in FUTURE weather forecasts.

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