Select the best way to revise the following sentence to achieve​ gender-neutral, unbiased language while maintaining pronoun agreement.
When a nurse becomes too emotionally attached to her​ patients, it becomes difficult for her to do her job effectively.
A.
No change is​ needed; the sentence is fine as it is.
B.
When nurses become too emotionally attached to their​ patients, it becomes difficult for him or her to do his or her job effectively.
C.
When a nurse becomes too emotionally attached to his or her​ patients, it becomes difficult for the nurse to do an effective job.
D.
When a nurse becomes too emotionally attached to their​ patients, it becomes difficult for them to do their job effectively.