sentence completion

[Trex]

----, the soldiers were caught almost entirely by surprise.

A) As the general had not trusted his scouts' information

B) Since the enemy had already been seen in the vicinity

C) Despite the weather being so difficult to see in

D) Having gained almost two years' battlefield experience

E) Knowing that there were no enemy soldiers in the area

I am stuck between B and E. What do you think?

[BobK]

If the soldiers were caught almost entirely by surprise, there must have been some reason for them not to expect an attack. That rules out both B and E. What might have led them to think they were safe?

b