The Asteroid Mathilde Has a Mean Density of Only 1300

Multiple Choice

The asteroid Mathilde has a mean density of only 1300 kg/m³, which is about half the density of rock. What is believed to be the reason for Mathilde's low density?

A) Mathilde is a "rubble pile," having been shattered by collisions with other asteroids.
B) Mathilde is a binary asteroid that is too far away for us to see the individual components; the low density is an illusion created by the space between the two rocky components.
C) Mathilde is composed of about 1/4 rock and 3/4 ice.
D) Mathilde is a primitive asteroid, composed of loosely aggregated dust grains from the early solar nebula.