When your Contrasting multiple objects, your looking for any differences that may or may not be their. Think Compare and Contrast if that helps, The answer to this is A
Making the contrasts means making comparison of the two or more objects on the basis of features they exhibit. A contrast and comparative account will reveal the similarities and differences between the two or more objects. The contrasts can be made on two or more identifiable physical features (such as (size, color, length, height, volume, shape and others) and chemical composition.
A scientist contrasts two or more objects so as to look the differences among them.
