Answer:
Whether a traffic light is green, yellow or red
Explanation:
Boolean variables are variables that can either take one out of two options at any given instance.
Analyzing the given options
1. Elevator:
Possible Directions = Up or Down; That's two possible values
But it can only move in one direction at a given instance.
This can be represented using Boolean
2. Traffic Light:
Possible Lights = Green, Yellow or Red
That's three options.
This can be represented using Boolean
The last two options can be represented using Boolean because they have just two possible values
Hence, option (B) answers the question
