What is a compound microscope?

A compound microscope (Option B) is an optical instrument that uses two sets of lenses—a primary objective lens near the specimen and an eyepiece lens near the observer’s eye—to magnify small objects. The objective lens gathers light from the specimen and forms a magnified real image, which the eyepiece lens further enlarges for the observer. This design allows for high magnification and resolution, essential for studying microscopic details in fields like biology, medicine, and materials science. Option A (microscope with one lens) is incorrect as it describes a simple magnifying glass. Options C (concave lenses) and D (convex lenses) are incorrect since compound microscopes typically use convex lenses in both the objective and eyepiece for image formation and magnification. Understanding the components and function of a compound microscope elucidates its role in scientific discovery and education, enabling the study of structures beyond the limits of human vision.