In amphibians, Organ of Jacobson is for

The correct option is smell.

Step-by-Step Explanation:

1. Understanding the Organ of Jacobson:
The Organ of Jacobson, also known as the vomeronasal organ, is an auxiliary olfactory sense organ found in many tetrapods, including amphibians, reptiles, and mammals.

2. Location and Anatomy:
In amphibians, this organ is developed as a specialized diverticulum or pouch off the main nasal cavity. It is lined with sensory epithelium similar to the olfactory epithelium but is structurally and neurally distinct, projecting to the accessory olfactory bulb in the brain.

3. Functional Mechanism:
The primary function of the Organ of Jacobson is chemoreception. It detects chemical stimuli (specifically non-volatile substances, prey odors, and pheromones) that are dissolved in moisture. Because it perceives these chemical signals from the environment, its sensory modality is classified as smell (olfaction).

4. Comparison with Other Senses:
- Temperature is sensed by thermoreceptors in the skin.
- Pressure is detected by mechanoreceptors (such as Pacinian-like corpuscles) in the skin.
- Sound is detected by the auditory system (specifically the tympanum and inner ear organs like the amphibian papilla).
Therefore, the Organ of Jacobson is specifically dedicated to the sense of smell.