Answer:
x=0 
C is correct
Explanation:
If x is the probability of an impossible event. 
Probability is defined between 0≤0≤1
The value of probability can't be negative or less than 0.
The value of probability can't be greater than 1. 
For impossible event probability must be 0 because event doesn't occur. 
Here, x is the probability of impossible event. 
Event is impossible. So, probability must be 0 
x = 0
Hence, The value of x is 0