What does the constant of proportionality represent?

a
The constant ratio of one variable quantity to another to which it is proportional (or the Unit Rate)
b
The value that says all of our ratios are equivalent
c
The number that tells us how fast something is moving
d
The relationship between two rates with no similar units

100 points please answer!!!!

What does the constant of proportionality represent a The constant ratio of one variable quantity to another to which it is proportional or the Unit Rate b The class=