Which element affects how much light reaches the sensor alongside exposure time?

The aperture size is a critical factor in determining how much light reaches the sensor in a camera system, in conjunction with exposure time. The aperture is essentially an opening within the lens that can be adjusted to allow more or less light to enter. This opening is measured in f-stops, with lower f-stop values indicating a larger aperture. A larger aperture permits more light to hit the sensor, enabling better performance in low-light situations and affecting the overall exposure of the image.

While other factors such as ISO setting and shutter speed also influence exposure, they do so in different ways. ISO determines the sensor's sensitivity to light, whereas shutter speed controls how long the sensor is exposed to light. Image resolution, on the other hand, pertains to the amount of detail in the image and does not directly influence the amount of light reaching the sensor during exposure. Therefore, in terms of affecting light intake alongside exposure time, aperture size stands out as the correct element in this context.