'Gapeworm' of poultry is

Answer: Option C

'Gapeworm' of poultry is Syngamus trachea.
A gapeworm (Syngamus trachea), also known as a red worm and forked worm, is a parasitic nematode worm that infects the tracheas of certain birds.
The resulting disease, known as "gape" occurs when the worms clog and obstruct the airway. The worms are also known as "red worms" or "forked worms" due to their red colour and the permanent procreative conjunction of males and females.