One Astronomical Unit and one Parsec are units of _____________.

length

The correct answer is option 3. length.

One Astronomical Unit (AU) and one Parsec (pc) are units of length used in astronomy to describe distances on an astronomical scale.

Astronomical Unit (AU) is defined as the average distance between the Earth and the Sun, approximately 149.6 million kilometers (about 93 million miles). It is often used to describe distances within our solar system, such as the average distance from Earth to other planets.

Parsec (pc) is a unit of length used to measure large distances outside our solar system, particularly in interstellar and galactic space. One parsec is approximately equal to 3.26 light-years or about 30.9 trillion kilometers (19.2 trillion miles). Parsecs are commonly used to describe distances to stars, galaxies, and other celestial objects beyond the solar system.

Both AU and parsec are crucial in astronomy for understanding and quantifying the vast distances involved in the universe.