**Core Concept**
The organ of Corti is a sensory organ in the cochlea responsible for sound processing, consisting of hair cells and supporting cells. The hair cells are crucial for converting sound vibrations into electrical signals. The supporting cells play a vital role in maintaining the structural integrity and function of the hair cells.

**Why the Correct Answer is Right**
The correct answer is based on the anatomy of the organ of Corti. The Deiters' cells, also known as phalangeal cells, are a type of supporting cell that provide structural support to the hair cells in the organ of Corti. They are located between the pillar cells and the hair cells and help maintain the proper position and function of the hair cells. The other options are not directly related to the supporting cells of the organ of Corti.

**Why Each Wrong Option is Incorrect**
**Option A:** Onodi cells are a type of cell found in the sphenoid sinus and are not related to the organ of Corti.
**Option C:** Hensen's cells are a type of supporting cell found in the cochlea, but they are not the primary supporting cells for the hair cells in the organ of Corti.
**Option D:** The bulla is a structure in the middle ear, but it is not related to the supporting cells of the organ of Corti.
**Option E:** The Haller's cell is a type of cell found in the macula of the utricle, which is part of the vestibular system, and is not related to the organ of Corti.

**Clinical Pearl / High-Yield Fact**
The organ of Corti is a complex structure that relies on the proper functioning of its supporting cells to maintain its sensitivity to sound vibrations. Damage to these supporting cells can lead to hearing loss.

**Correct Answer:** B. Deiter cell