Study the following statements.
a. The body is dorsoventrally flattened.
b. Hooks and suckers are present in parasitic forms.
c. Flame cells help in excretion and osmoregulation.
d. Fertilisation is internal.
The above are the general characters of the phylum

The given features are the general characters of the phylum Platyhelminthes. 

They have dorso-ventrally flattened body. 

Hooks and suckers are present in the parasitic forms. 

Specialised cells called flame cells help in osmoregulation and excretion. 

Fertilisation is internal and development is through many larval stages.