Step 1: Understanding dance forms.
Kathak, Mohiniyattam, and Odissi are all recognized classical dance forms of India.
Step 2: Explanation.
Thumri, however, is not a dance form but a semi-classical vocal music style that originated in North India, characterized by its romantic and devotional themes.
Step 3: Conclusion.
Therefore, Thumri is not a dance form.