The correct answer is: B. Inertia of motion.
Inertia is the tendency of an object to resist any change in its motion. When a bus takes a sudden turn, the passengers inside the bus tend to continue moving in a straight line due to inertia. This causes them to be thrown outward.
Option A is incorrect because there is no outward pull on the passenger. The passenger is simply moving in a straight line and is then forced to change direction by the bus’s turn.
Option C is incorrect because the passenger’s momentum does not change. The passenger’s momentum is simply in the wrong direction.
Option D is incorrect because the passenger’s acceleration does not change. The passenger’s acceleration is simply in the wrong direction.