For those who lacked academic prowess in high school, a two-year community college course may instill a valuable sense of discipline and open doors to better opportunities in the future.
(A) may instill a valuable sense of discipline and open doors to better opportunities in the future
Correct choice: “may instill” and “open” are parallel.
(B) might instill for them a valuable sense of discipline and to open doors to better opportunities in the future
“for those” and “for them” are redundant. “to open” isn’t parallel to “might instill”.
(C) may, in them, instill a valuable sense of discipline, opening their doors to better opportunities in the future
“in them” is incorrectly turned into an adverbial mod. “their” should have the same referant as “them” which is “those”. but “doors” are not of “those”.
(D) opening the door later for a better opportunity and giving them a valuable sense of discipline now
This choice is a fragment because it lacks a verb.
(E) may open the door for a better opportunity later and giving them a valuable sense now of their discipline
“may open” and “giving” are not parallel.
Hence A