Sentence Correction (SC) | The type of behavior exhibited when an animal recognizes itself

The type of behavior exhibited when an animal recognizes itself in a mirror comes
within the domain of “theory of mind,” thus is best studied as part of the field of
animal cognition.
A. of “theory of mind,” thus is best
B. “theory of mind,” and so is best to be
C. of a “theory of mind,” thus it is best
D. of “theory of mind” and thus is best
E. of the “theory of mind,” and so it is best to be

Can someone please help me with this question. Thanks

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