Friction is a force that opposes the relative motion between two surfaces in contact. It acts parallel to the contact surface and in the opposite direction to the applied force. Friction is a common phenomenon that we experience in our daily lives. It plays a significant role in our ability to walk, drive vehicles, and perform various tasks.

Friction and Relative Motion:
Friction arises when there is relative motion or an attempt of relative motion between two surfaces in contact. When an object is at rest, the force required to put it in motion is known as static friction. Once the object is in motion, the force required to keep it moving is called kinetic friction. In both cases, friction acts in the opposite direction to the applied force.

Explanation:
Friction opposes relative motion because it arises due to the microscopic irregularities present on the surface of objects. When two surfaces are in contact, these irregularities interlock with each other, making it difficult for one surface to slide or move over the other. As a result, a force of friction is generated, which opposes the motion or potential motion between the surfaces.

Friction and Different Types of Motion:
a) Reflective Motion: Reflective motion is not a commonly used term in physics or mechanics. It does not relate to the concept of friction, so option 'a' is incorrect.

b) Relative Motion: Relative motion refers to the motion of an object with respect to another object. Friction always opposes the relative motion between two surfaces in contact. Therefore, option 'b' is correct.

c) Rotary Motion: Rotary motion refers to the circular or rotational motion of an object around an axis. Friction can also act to oppose rotary motion by providing a resistive force to the rotation. However, the question specifically mentions "between two surfaces in contact," implying linear or translational motion. Therefore, option 'c' is incorrect.

d) Refractive Motion: Refraction is the bending of light as it passes from one medium to another. Refractive motion is not a term related to friction or motion between surfaces. Hence, option 'd' is incorrect.

In conclusion, friction opposes the relative motion between two surfaces in contact. It acts as a resistive force that opposes the motion or potential motion between the surfaces.