单选题 Experts removed a layer of eighteenth-century red paint from a figure in a painting by a sixteenth-century Italian artist, revealing a layer of green paint underneath. Since the green paint dates from the sixteenth century, the figure must have been green, not red, when the painting was completed in 1563.
Which of the following, if true, most seriously weakens the argument?

A、 The experts had been commissioned to restore the painting to the colors it had when it was completed.
B、 X-rays reveal an additional layer of paint beneath the green paint on the figure.
C、 Chemical analyses were used to determine the ages of the red paint and the green paint.
D、 The red paint was added in the eighteenth century in an attempt to repair damage done in the late seventeenth century.
E、 (E) Red paint on the robe of another figure in the painting dates from the sixteenth century.

【正确答案】 B

【答案解析】[解析] 本题推理关系为“去除了一层18世纪加上的红颜料后发现下面有一层绿色颜料，所以说人物像完成时为绿色。”属于“B，A”型的反对，思维切入点为“除了A以外还有别的原因导致B”，用B中关键词green paint定位，排除了(A)、(D)和(E)；而(C)说明不了任何问题；(B)指出绿色下面还有一层颜料，说明绿色可能是后来加上的，反对了结论，因此(B)正确。