Statement I :Majority of parasites harm the host by reducing its survival, growth, and reproduction.

Statement II :The human liver fluke depends on two intermediate hosts, a snail and a fish, to complete its life cycle. 

Both statement I and statment II are correct .

 Both the Statements are correct.

Parasites have evolved to exploit their hosts for their own survival and reproduction. By taking nutrients and resources from the host, parasites can negatively impact the host's fitness. They can cause various harmful effects on the host, including decreased survival rates, hindered growth, and reduced reproductive success. These detrimental effects ultimately benefit the parasite by ensuring its own survival and reproduction.

Statement II: The human liver fluke depends on two intermediate hosts, a snail and a fish, to complete its life cycle.

This statement is also true. The human liver fluke (a trematode parasite) has a complex life cycle that involves two intermediate hosts. The adult fluke lives in the liver of humans and other mammals, where it produces eggs. These eggs are then excreted through feces and released into water. In freshwater environments, the eggs hatch, and the larvae seek out a specific species of snail, which serves as the first intermediate host. Inside the snail, the larvae undergo several developmental stages and reproduce asexually. The larvae are then released from the snail and swim freely in the water. If they encounter a suitable fish, they penetrate the fish's tissues and transform into the infective stage for humans. When humans consume raw or undercooked infected fish, the larvae are released in the human intestines and migrate to the liver, where they mature into adult flukes, completing the life cycle.

Overall, the human liver fluke's complex life cycle involving two intermediate hosts is an adaptation that ensures its successful reproduction and transmission between hosts.