When the long axis of the head is vertical and the mouth parts ventral, such type of orientation is known as:

Correct option is A

In insect morphology, head orientation is classified based on the position of the mouthparts relative to the long axis of the head and the body. When the head is positioned vertically downward and the mouthparts are directed ventrally (toward the ground), the orientation is referred to as hypognathous.
�� Head Orientations in Insects:
1. Hypognathous ✅
· Long axis of the head is vertical.
· Mouthparts are directed downward.
· Common in orthopterans like grasshoppers and locusts.
· Suited for feeding on surfaces below the head.
2. Prognathous ❌
· Mouthparts directed forward (anteriorly).
· Found in predatory insects like ground beetles.
· Helps in seizing prey ahead of the body.
3. Opisthognathous ❌
· Mouthparts directed backward beneath the body.
· Seen in hemipterans (e.g., plant bugs) with piercing-sucking type mouthparts.
4. Clypeus ❌
· Not a type of orientation.
· It is a specific part of the insect head, located between the frons and the labrum, involved in supporting mouthparts.