What would happen if two normal colliders collide in Unity?

When two normal colliders collide in Unity, they will result in a physical collision response. This is because Unity’s physics engine is designed to handle interactions between colliders using realistic physics simulation. When colliders intersect, they essentially trigger a collision event that allows the physics engine to calculate the resulting forces, which can lead to movement, bouncing, or other interactions depending on the objects' mass, velocity, and material properties.

This physical response can involve both rigid body physics and interactions determined by the properties of the colliders, such as whether they are set to trigger or the material they are using. The physics engine simulates how these objects should behave according to natural laws, making this an essential part of game development in Unity.

The other options lack the appropriate functionality provided by Unity's physics system. For instance, overlapping without any response would imply no interaction at all, which does not reflect the expected behavior of colliders in a physical environment. Similarly, creating a visual effect alone does not incorporate the dynamic interactions expected from physical colliders and does not leverage Unity’s physics capabilities. Disabling colliders automatically after a collision doesn't align with standard physics behavior either, as colliders are meant to react and potentially continue to interact unless specifically coded to do otherwise.