Which of the following is incorrect with respect to Model Checking ?

Which of the following is incorrect with respect to Model Checking ?

A. Model checking is particularly valuable for verifying concurrent systems
B. Model checking is computationally very inexpensive
C. The model checker explores all possible paths through the model
D. All of the mentioned

Explanation: Model checking is very expensive.It is only practical to use it in the verification of small to medium sized critical systems.