Answer:
the best answer is a. F-9, ISO 100. This is because aperture priority mode allows you to control the aperture and ISO, while the camera automatically adjusts the shutter speed. For landscape photography, you want to use a high f-stop (such as f/9) to get a large depth of field and a sharp focus. You also want to use a low ISO (such as 100) to reduce noise and increase dynamic range. The other options are not suitable for landscape photography because they either use a low f-stop (such as f/2.8 or f/1.4) which creates a shallow depth of field and a blurry background, or a high ISO (such as 3200 or 800) which introduces noise and reduces dynamic range.