Which of the following is an example of parallel structure?

susan climbs up the stairs, opens the door, and turned on the light.
susan climbs up the stairs, opened the door, and turns on the light.
susan climbed up the stairs, opens the door, and turns on the light.
susan climbed up the stairs, opened the door, and turned on the light.

answer; i believe that the correct answer is (scientific data);

explanation:

you only need simple sentences to answer this. just answer these questions.

what do you think annie thinks of the mother? do you think annie believes the mother is a fit mother for helen.

what about the father? what would annie think of him? she might not like him, but does she respect him.

how about the son? would annie think he is the only voice of sanity in an insane place?

what about helen herself? this is the key question. how does she see helen? what do you suppose she thought her first job was going to be.

these aren't hard questions. just state the obvious. annie is not that well educated: she just knows what she has to do. write it that way.

you can do it if you've read the book or seen the play or movie.