The ratio of inertial mass to the gravitational mass is equal to:

Explanation

Inertial mass is a measure of how fast an object accelerates--given the same force, increasing the inertial mass implies decreasing acceleration. The simplest way to state the equivalence principle is this: inertial mass and gravitational mass are the same thing.The inertial mass and gravitational mass of an object are identical in value, so their ratio is 1. They differ in how they are measured. Inertial mass is measured by measuring an object's resistance to changes in velocity; while gravitational mass describes the force on an object in a gravitational field.A, C, D: These options are incorrect as they do not state the true value of the ratio i.e. 1.