user
I am called white.  My duty is to protect and destroy.  All it takes is a sneeze and i will destroy. . .  at the sign of a cut, i will come to protect.  I will fight to my death. . .  no matter how insignificant it may be.  I am very helpful yet you can't see me.  What am i?
A: place
B: white blood cell
C: role
D: edge
E: separate
assistant
<|begin_of_thought|>

Deep Thought is thinking for 7.5 million years.

<|end_of_thought|>

<|begin_of_solution|>

B

<|end_of_solution|>