Final answer:
The branching factor for 2 Pac-Men who can each make one of 5 choices (North, South, East, West, Stop) is 25, which is the result of multiplying the number of choices one Pac-Man has by itself because the choices are independent.
Step-by-step explanation:
The branching factor in a decision tree represents the number of choices available from any given point (or node). In the context of Pac-Man, if each Pac-Man can choose to go North, South, East, West, or Stop, this gives us a total of 5 different actions one Pac-Man can take. Since there are 2 Pac-Men and each has these 5 options independently, we calculate the branching factor by multiplying the number of options one Pac-Man has by itself because the choices are independent. Therefore, the branching factor for 2 Pac-Men would be 5 (choices for the first Pac-Man) times 5 (choices for the second Pac-Man), resulting in a total branching factor of 25.