Write one example for each of the following in the space provided:
$(a)$ Cold-blooded animal.
$(b)$ Warm-blooded animal.
$(c)$ Animal possessing dry and cornified skin.
$(d)$ Dioecious animal.

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:

Which of the following is considered a living fossil?

In which one of the following is the genus name,its two characters,and phylum $NOT$ correctly matched?

Which of the following statements is correct for the given animal group?

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

Column $X$	Column $Y$
$(1)$ Green gland	$(P)$ Mollusca
$(2)$ Digestive tract with digestive glands	$(Q)$ Arthropoda
$(3)$ Straight or coiled alimentary canal	$(R)$ Hemichordata
$(4)$ Straight or $U$-shaped digestive tract	$(S)$ Echinodermata