Veterans return to civilian life after serving in combat zones. they may have physical issues, including lost limbs or brain damage, or suffer from

Post traumatic stress disorder.

Explanation:

Post traumatic stress disorder, or PSTD is a disorder that affect psychologically a great number of people that have lived throug though times and then they go back to their reality and their minds think they are still in that traumatic situation, it happens with soldiers after they have left the battlefield and are still anxious and paranoid like if they were still there, or with people that have lived throug accidents and feel like they are still in the same situation.

c) science positively influencing society