The correct answer is A. Light year.
A light year is a unit of astronomical distance equivalent to the distance that light travels in one year, which is 9.4607 Ã 1012 km (nearly 6 trillion miles). It is used to measure distances to stars and other objects outside the Solar System.
An angstrom is a unit of length equal to one ten-billionth of a meter (10â10 m). It is used to measure the wavelengths of light and other electromagnetic radiation.
A weber is a unit of magnetic flux in the International System of Units (SI). It is equal to the magnetic flux through a surface of one square meter when the magnetic field perpendicular to the surface is one tesla.
A lux is a unit of illuminance in the International System of Units (SI). It is equal to one lumen per square meter. Illuminance is a measure of the amount of light that is incident on a surface.