A collider is required to:

A) make walls impassible
B) make walls invisible
C) create objects in unity
D) all of the above

A) make walls impassible

Explanation:

In unity, we can use a collier to make an impassible wall or other objects, for example, if we have a wall or floor of ice will be slippery, but this object won't be deformed, and we can add this collider in a ball, this object will have physic but this won't be deformed, the collider is invisible but the object is physic.

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