I am not able to find a sureshot guideline for when to use 'as' and when 'like'.
In Manhattan sentence correction, an explaination is given for it. It says that if nouns are being compared 'like' is to be used. But when it is verb or adverb, 'as' has to be used and 'like' will be gramatically wrong there.

In Q. no. 126 of OG, right answer is the one which uses 'like' for comparing verb with a noun.

More than thirty years ago Dr. Barbara McClintock, the Nobel Prize winner, reported that genes can
"jump," as pearls moving mysteriously from one necklace to another.
(A) as pearls moving mysteriously from one necklace to another
(B) like pearls moving mysteriously from one necklace to another
(C) as pearls do that move mysteriously from one necklace to others
(D) like pearls do that move mysteriously from one necklace to others
(E) as do pearls that move mysteriously from one necklace to some other one

Shall it not be a comparision 'between a verb and a verb' instead of between 'a verb and a noun'. And 'as' shall be used for adherence to grammar. This is exactly done by choice E. Although E is slightly awkward in construction but is grammatically correct and so should be preferred over somethign which is gramatically incorrect (B).
OA is B.
Can somebody explain me why?