! based on the following table, which object has the lowest density? a. object a b. object b c. object c d. object d

The answer to this question lies in the definition of density. One material will just float over another if its density is smaller. If one material is denser than the other, it will sink. Density can be defined as the mass per unit volume of a substance at a given pressure and temperature. Thus, for a material to float in water, it does not depend on the weight, or rather on the mass, but on the distribution of the mass by the volume occupied, that is, of the density. The more distributed the mass, that is, the larger its volume, the less dense the object and it will float.

Object C has the lowest density
65 N or 6.5 Kg 6 N or 6 Kg

This effective mass under water will be its actual mass minus the mass of the fluid displaced. 

The buoyant force on a submerged object is equal to the weight of the fluid displaced.
Weight of object - buoyant force on object (the mass of the fluid displaced)

6Kg - 6.5Kg= - 0.5Kg

 C. object C