Answer: Annelida
Leeches are soft bodied segmented parasitic worms. They belong to the phylum Annelida. They are hermaphrodites which means they exhibit sex organs of both male and female.
The characteristics which are found in leeches which group them into Annelida are:
1. The body of the leeches are bilaterally symmetrical like other Annelids. The body organs are also segmented.
2. They have a closed circulatory system in which the heart pumps the blood to all the parts of the body.
3. Leeches either exhibit a protusible pharynx or proboscis which allows them to suck the blood of the host such features are also common in other Annelids.