Answer : 3. "असम"
Explanation :

1. Kamakhya Temple is a Hindu temple located on the Neelachal Hills in Guwahati, Assam.

2. This temple is dedicated to Goddess Kamakhya, it is one of the oldest and most revered centres of Tantric practices.

3. This temple is the centre of Kulachar Tantra Marg and the venue of Ambubachi Mela