Neck is not found in a frog. This absence helps the frog to

The correct option is "jump on ground".

Detailed Explanation:

Frogs are specialized for a saltatorial mode of locomotion, which means they move by jumping and leaping on land. When a frog jumps, it experiences a significant impact force upon landing. The absence of a neck in frogs means that their head is fused directly to the trunk without a flexible cervical region.

This structural adaptation serves a critical biomechanical function: during landing, the shock of the impact is transmitted directly through the rigid, continuous vertebral column to the rest of the body. If a frog had a flexible neck, the sudden deceleration during landing would cause the head to bend violently forward or backward, potentially injuring the spinal cord or brain. Therefore, the lack of a neck provides structural rigidity that helps the frog safely jump on the ground by absorbing the landing shock.