A scalar quantity is a quantity that has magnitude only but no direction, while a vector quantity is a quantity that has both magnitude and direction:
Let's go through the choices:
Displacement: you can move from one point to another towards east, west, north,....etc. This means that displacement has both magnitude and direction. (vector)
Time: time has no direction whatsoever. (scalar)
Velocity: velocity is mass*acceleration. The acceleration can be towards any direction. Your velocity can be towards any direction. Since acceleration is vector, therefore, velocity is also a vector quantity.
Force: a force can push a body right, left,...etc. This means that the force has a direction as well as a magnitude. (vector).
Based on the above, the scalar quantity is:
(B) Time
