Which of the following phyla possess an open circulatory system?
$(a)$ $Arthropoda$
$(b)$ $Annelida$
$(c)$ $Chordata$
$(d)$ $Mollusca$

$A$: Annelids and Arthropods exhibit bilateral symmetry.
$R$: In Annelids and Arthropods,the body can be divided into identical halves through any plane passing through the central axis.

Match the following group of organisms with their respective distinctive characteristics and select the correct option:

Organisms	Characteristics
$(a)$ Platyhelminthes	$(i)$ Cylindrical body with no segmentation
$(b)$ Echinoderms	$(ii)$ Warm-blooded animals with direct development
$(c)$ Hemichordates	$(iii)$ Bilateral symmetry with incomplete digestive system
$(d)$ Aves	$(iv)$ Radial symmetry with indirect development

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 one of the following is $NOT$ an adaptation in endoparasitism?

Identify the correct terms for the following analogy-based questions:
$(i)$ In Porifera: Water exits through Osculum :: In Cnidaria: ......
(ii) Ctenophora: Comb plates :: Aschelminthes: ......