Which of the following is a method to optimize performance in Unity?

Minimizing the use of real-time lights is indeed a key method for optimizing performance in Unity. Real-time lights require continuous calculations every frame to determine how they illuminate the environment, which can significantly impact performance, especially in scenes with multiple light sources or complex geometries. By limiting the number of real-time lights or opting for baked lighting solutions where appropriate, you can reduce the computational load on the engine, leading to smoother frame rates and better overall performance.

In contrast, increasing draw calls adds more overhead to the rendering process, complex shaders can increase the processing time for each pixel rendered, and adding more Rigidbody components can lead to a heavier physics simulation, all of which can negatively affect performance rather than optimize it.