Can you beat this one?

Which choice best states the main idea of the text?

1. AThe face and background show wavering lines that were reworked several times, unlike the steadier, more confident brushwork in the hands and dress.
2. BInfrared imaging has revealed that most seventeenth-century portraits attributed to single painters were actually produced by multiple hands.
3. CInfrared imaging points to more than one hand painting the portrait, though the museum has not revised its single-painter attribution.
4. DBecause the museum has not changed the painting's wall label, curators apparently reject the idea that more than one painter worked on it.