Which of the following correctly differentiates between diploblastic and triploblastic animals?
Diploblastic animals (e.g., Cnidaria) have only two germ layers: ectoderm and endoderm. Triploblastic animals (e.g., Platyhelminthes and above) have an additional mesoderm.
Ref: NCERT Class 11 Biology Chapter 4: Animal Kingdom Basis of Classification - Symmetry Coelom Segmentation