When a dog from the Grange attacks Cathy at her intrusion, the Lintons help her by keeping her at the Grange for five weeks. This visit permits Cathy to transform into a woman very not at all like the inconsiderate, wild, puerile young lady she has been with Heathcliff and enables her to frame close relationships with Edgar and Isabella Linton, the two youngsters living at the Grange, despite the fact that her (and Heathcliff's) beginning impression of them was disdainful.
The correct sentence is (A). In this example the author stablishes a good parallel structure when he/she enumerates the items. Commas must not be used in an independent clause; in particular, before a verb (the comma before “were” is not correct as an example B).
