Although the Impressionists painters appeared to earlier art

[Sentence_Completion]

Although the Impressionists painters appeared to earlier art historians to be [color=red]unstudied in their methods, recent analyses of their brush work suggest the contrary ? that, in fact, their technique was quite [color=red]sophisticated.
(A) unstudied. .sophisticated (B) idiosyncratic. .effective © eclectic. .naïve (D) lax. .fashionable (E) careless. .unpremeditated

What is the problem with the © option?

[Luschen]

@Sentence Completion

Although the Impressionists painters appeared to earlier art historians to be [color=red]unstudied in their methods, recent analyses of their brush work suggest the contrary ? that, in fact, their technique was quite [color=red]sophisticated.
(A) unstudied. .sophisticated (B) idiosyncratic. .effective (C) eclectic. .naïve (D) lax. .fashionable (E) careless. .unpremeditated

What is the problem with the (C) option?

Hi, the words “although … .contrary” mean that the two words in the answer need to be opposites. The only opposites among the choices are unstudied/sophisticated. “Naive” in an art context usually means primitive or untrained while eclectic means combining many styles together, so these words are not opposites, and actually not really related at all.