The Microscope's ability to distinguish between separate objects that are close together is called:

Explanation

The correct answer is resolving power or resolution. Resolution refers to a microscope's ability to distinguish between two points that are close together. It is a key factor in visualizing fine details and is dependent on the microscope's optical properties, such as numerical aperture and the wavelength of light used. In contrast, magnification increases the size of the image without necessarily improving clarity. Contrast enhances visibility by differentiating the specimen from its background but does not affect resolution. Scanning power involves a lower magnification level for initial scanning and does not pertain to resolving power.