Answer:
It's the oesophagus.
Explanation:
The worm digestive system consists of the pharynx, the esophagus, the crop, the intestine and the gizzard. The oesophagus is not mentioned. Thus, it's not part of the worm digestive system.
1. NA = Sodium, NA was the chemicals symbols for the element would be NA because in Latin it is natrium for natron in which is sodium in English, Sodium was created by Humphry Davy in the year of 1807. Element name Sodium, Chemical symbol NA atomic number, 11 Atomic mass 23.
2. AG = Sliver, AG was the chemicals symbols for the element would be AG because in Latin it is argentum in which in English means bright and also sliver. Element name Sliver Chemical symbol AG atomic number, 47 Atomic mass 108.