10. The work of mathematician Roger Penrose in the early 1970s, on the geometry of what are called aperiodic tiles, turned out to describe the architecture of a previously unknown class of crystals.
(A) what are called aperiodic tiles, turned out to describe
(B) what is called aperiodic tiles, describes
(C) aperiodic tiles, describing
(D) so-called aperiodic tiles, describe（A）
(E) aperiodic tiles, it turned out to describe
这道题目我看了以前很多讨论，但还不是很理解，查过字典关于turn out，有prove to be, “原来是，证明是”的含义，这里是否因为要表达这种意思所以要保留turn out呢，就和remain, become等词一样，还请各位赐教。 | 
