Sentence Correction (SC) | Re: Although similar ancient camel art has also been found in Yemen and Om

A. being studied by a group of French researchers and that is stylistically unique - Not a sentence. Missing verb error. Subject 'engravings' does not have a verb.

B. being studied by a group of French researchers that is stylistically unique - Same as A + Illogical to say that a group of French researchers is stylistically unique.

C. that is being studied by a group of French researchers and is stylistically unique - Same as A

D. that is being studied by a group of French researchers – is
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