Which of the following organisms exhibits body segmentation?

Given below are two statements:
Statement $I$: When any plane passing through the central axis of the body divides the organism into two identical halves, it is called radial symmetry.
Statement $II$: In phylum Echinodermata, both adults and larvae are radially symmetrical.
In the light of the above statements, choose the most appropriate answer from the options given below:

An animal that is initially male and then changes to female is called:

Which of the following statements is incorrect?

Which one of the following is a matching set of animals belonging to the same phylum?

Select the correct match for Column $X$ and Column $Y$:

Column $X$	Column $Y$
$(1)$ Aves	$(A)$ Endoskeleton made of cartilage
$(2)$ Amphibia	$(B)$ Left aortic arch
$(3)$ Chondrichthyes	$(C)$ First homeothermic animals
$(4)$ Mammalia	$(D)$ Metamorphosis