Question

mrs hale: (looking about) it never seemed a very cheerful place.
county attorney: no - its not cheerful. i shouldnt say she had the homemaking instinct.
mrs hale: well, i dont know as wright had, either.
county attorney: you mean that they didnt get on very well?
mrs hale: no, i dont mean anything. but i dont think a placed be any cheerfuller for john wrights being in it.
how does this dialogue develop mrs. wrights possible motivation for killing her husband?
the dialogue suggests that mr. wright was constantly unhappy.
the dialogue suggests that mrs. wright may have desired to escape her unhappy marriage.
the dialogue suggests that mrs. wright may have wanted to prove her abilities.
the dialogue suggests that mrs. wright may have wanted to assert her independence.

Explanation:

The dialogue shows that the place (home) wasn't cheerful. Mrs. Hale implies that John Wright (Mr. Wright) didn't make the place better. This suggests an unhappy environment (marriage). The mention of the home - making instinct and the lack of cheerfulness points towards an unhappy marriage situation.

Answer:

The dialogue suggests that Mrs. Wright may have desired to escape her unhappy marriage.