According to the given information,
I. Four girls are sitting in a circle and facing towards the center.
II. Kirti is sitting to the right of Suhani.
III. Kirti is not sitting to the left of Vatshala, So Vatshala is not to the right of Kirti.
IV. Anushka is sitting between Kirti and Vatshala.
So, Suhani is sitting to the right of Vatshala.
Hence, the correct answer is "Suhani".