The study of worms which cause parasitic infestations in humans is called:

Consider the following characters $:-$
$1.$ Bilateral symmetry
$2.$ Acoelomate
$3.$ Incomplete digestive system
$4.$ Mostly endoparasites
Select the correct group of phylum with its corresponding animal for the above-given characters $:-$

Pseudocoelom is not found in

Flame cells are the excretory organs of:

Mostly hermaphrodite animals are present in

The liver fluke ($Fasciola$ $hepatica$) completes its life cycle in which two hosts?