The correct answer is A. Opaque.
Opaque objects do not allow light to pass through them. Examples of opaque objects include walls, books, and tables.
Translucent objects allow some light to pass through them, but they do not allow you to see clearly through them. Examples of translucent objects include frosted glass, wax paper, and some plastics.
Solid objects have a definite shape and volume. They do not flow or change shape easily. Examples of solid objects include rocks, water, and wood.
Fragile objects are easily broken or damaged. Examples of fragile objects include glass, china, and eggs.
In the case of the window-pane, it is transparent because light can pass through it easily and you can see clearly through it.