Question 622122
I will say the first two are and the last one is not.
The first two have a list of values, where the probabilities are all between 0 and 1 with a total of all listed of 1 or less. For those first two, assuming there are other values of x which are NOT shown, the listed values are between 0 and 1 AND their total is less than 1.

The third one has a probability entry (the secocd one) less than 0. The total is 1, but you can't have a probability less than 0.