Answer:
mass
Explanation:
We see the definitions for each option.
Weight: Weight is the force with which earth attracts a body towards itself. Weight changes with the value of acceleration due to gravity.
Mass: Mass is defined as the quantity of matter contained in a body. It remains constant anywhere in the universe.
Time: The interval of time that passes on
Length: Distance between two specified points.
Hence, it is clear from the definition that the physical quantity that represents the quantity of matter is:
mass
