When trying to create a steady stream of particles, fixing gaps in emission can involve adjusting which of the following settings?

Adjusting the "Rate Over Time" setting is essential for creating a consistent emission of particles in Unity. This setting directly controls the number of particles emitted per second, allowing you to fill gaps in the stream effectively. When you increase the rate, more particles are spawned, which can help create a continuous flow and reduce any noticeable breaks in the emission.

By focusing on the rate of emission, you can ensure that particles are being generated at an optimal frequency, maintaining a steady visual effect. If the rate is too low, it can lead to visible gaps, while a balanced rate will help maintain the desired appearance of a seamless stream.

The other settings, while important for various particle effects, do not specifically target the issue of gaps in the emission stream in the same direct manner. For instance, "Start Size" impacts the size of the particles, which does not affect their emission frequency, and "End Lifetime" determines how long particles persist before disappearing, influencing the lifespan rather than the emission rate. "Emission Shape" describes the area from which particles are emitted, impacting the direction and spread but not the number of particles produced over time. Therefore, adjusting the "Rate Over Time" is the most effective method to fix emission gaps.