Liver fluke is a parasitic flatworm that affects the liver of humans and animals. It has a complex life cycle that involves different stages of development. The larval stages of liver fluke are important for understanding the transmission and pathogenesis of the disease.

The correct answer is option C, which is cercaria.

Explanation:

• Redia: It is the first larval stage of liver fluke. It is a sac-like structure that develops inside the snail host after the ingestion of eggs by the snail.

• Miracidium: It is the second larval stage of liver fluke. It develops from the redia and leaves the snail host to infect the intermediate host, which is usually a freshwater snail.

• Cercaria: It is the third larval stage of liver fluke. It develops inside the freshwater snail and leaves the snail to infect the final host, which is usually a mammal, including humans.

• Metacercaria: It is the fourth larval stage of liver fluke. It develops from the cercaria and encysts in the vegetation or other substrates. The final host becomes infected by ingesting the metacercaria.

Therefore, the correct answer is cercaria, which is the third larval stage of liver fluke. It is important to understand the different stages of the life cycle of liver fluke for effective control and prevention of the disease.

Order of larval stages are miracedium,sporocyst,redia,cercaria,metacercaria.so ,dipinnaria is not larval stages of liver fluke.