Consider following features: (a) Organ system level of organisation (b) Bilateral symmetry (c) True coelomates with segmentation of body. Select the correct option of animal groups which possess all the above characteristics.

Correct option is A. Annelida, Arthropoda and Chordata. True segmentation is present in Annelida, Arthropoda and Chordata. They also have an organ-system level of organisation, bilateral symmetry and are true coelomates. On the other hand, molluscs have an unsegmented body. So, the correct answer is 'Annelida, Arthropoda and Chordata'.