Which of the following is a scalar quantity? a.) displacement b.) time c.) velocity d.) force

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

Element B is present in sample one.
Element A and D are present in sample two.
Sample three contains element C.
Sample four contains elements A, B, and C