Sentence Correction (SC) | Re: On Earth, among the surest indications of sunspot cycles are believed

Contenders C and E

C)On Earth , the rate at which trees grow is believed to be among the surestindications of sunspot cycles ,as seen in the rings visible in the cross sections of theirtrunks.

Issue 1: Meaning

Essentially, in the first part of the sentence,On earth, <A> is believed to be <B>.... ,
which illogically implies that
On earth A is believed to be B, but somewhere else it could be C the true meaning intended is: Surest indication of <something> on earth is believed
...

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