Determining if an object will float or sink is based on the density of the object and also the density of the solution, the lower the density, more likely the object is to float, and if the density is higher, therefore the object is heavier and it will sink. In our question we have ebony wood with a density of 1.2, the only possible layer that this material can float is on Chloroform, that has a higher density, therefore the answer is letter A