Only when he was told that his precious stone was but an artificial gem did the old man realize that he had been cheated of almost RMB 100,000 yuan.

题目
Only when he was told that his precious stone was but an artificial gem did the old man realize that he had been cheated of almost RMB 100,000 yuan.

A: superficial
B: custom-made
C: ready-made
D: man-made