The correct answer is C. the aftereffects of combat on soldiers during war.
If you are in k12, the answer is:
"Ben looked forward to discovering which route they would take and which unique places they might visit this year."
C because a compound sentence is when you have once sentence, but it can become two. it is separated by commas (,)
1. I go to the park 2. i run there with my friends 3. i wear a normal shirt 4.a water park 5. I ate lots of foods