987-87 和987-60对distinguish from/bwtween的困惑

本来对distinguishing 用法挺清楚的，打从看到987-60

60.        After a few weeks’ experience, apprentice jewelers can usually begin to discriminate, though not with absolute certainty, genuine diamonds from imitation diamonds.

(A) genuine diamonds from imitation diamonds

(B) genuine diamonds apart from imitations

(C) between genuine diamonds and imitation diamonds

(D) among genuine diamonds and imitation diamonds（C）

(E) whether diamonds are imitation or genuine

这里选了discriminate between，看了大家的讨论，结论是这个前后区分对象没从属关系，否则就偏向discriminate from，受其影响，俺做987-87时选了D

1.        Although many art patrons can readily differentiate a good debenture from an undesirable one, they are much less expert in distinguishing good paintings and poor ones, authentic art and fakes.

(A) much less expert in distinguishing good paintings and poor ones, authentic art and

(B) far less expert in distinguishing good paintings from poor ones, authentic art from

(C) much less expert when it comes to distinguishing good paintings and poor ones, authentic art from

(D) far less expert in distinguishing good paintings and poor ones, authentic art and（B）

(E) far less the expert when it comes to distinguishing between good painting, poor ones, authentic art, and，可是这个时候答案偏偏又是distinguishing from，ETS解释到也够简单

The best answer will follow the idiomatic form distinguishing X from Y. The substitution of and for from makes choices A, C, D, and E faulty. Moreover, far is a better modifier of less expert than much is in A and C, when it comes to distinguishing is wordy in C and E, and E fails to acknowledge that two distinctions are being considered – one between good and poor paintings, another between authentic art and fakes. B is the correct answer or this question of middle difficulty.有点糊涂了，到底怎么来判定是BETWEEN OR FORM 那？？

distinguish between A and B

distinguish A from B

我觉的用from 的时候,不一定要有从属关系.

第一题的问题是,我觉得,应该改成discriminate immitation diamonds from genuine diamonds.

discriminate from ?

not distinguish from?

查了字典，discriminate from是使有区别

Wings and feathers discriminate birds from other animals。

It is difficult to discriminate between区别，辨别 people emplyed in the same firm。，这里第一题不可能是学徒使真品和赝品有区别，肯定是区别，所以选了between，至于distingusih from/between就不清楚了，都有，意思相近，估计ETS喜欢前者

I also have the same confusion about the usage of discriminate/distinguish between X and Y, or X from Y.

Can somebody explain? Thanks!