See the following binomial tree. Yellow (top) for stock price, green (middle) for European put option premium, and blue for American put option premium (bottom).

What is the strike price?

A.

0.69494+0.05506 = 0.75

B.

0.78+0 = 0.78

C.

0.87547+0 = 0.87547

D.

1.10291+0 = 1.10291

1.10291 O O 0.98263 10 0.87547 IO 10.87547 0.0134 O 0.78 0.0134 0.78 O 0.04365 0.02716 0.02716 0.04507 0.69494 0.07508 0.07795 0.69494 0.05506 0.05506 0.61915 0.12503 0.13085 0.55163 0.19837 0.19837