Drainage

Below are given names of a few lakes of India. Group them under two categories
– natural and created by human beings.
(a) Wular (b) Dal
(c) Nainital (d) Bhimtal
(e) Gobind Sagar (f) Loktak
(g) Barapani (h) Chilika
(i) Sambhar (j) Rana Pratap Sagar
(k) Nizam Sagar (l) Pulicat
(m) Nagarjuna Sagar (n) Hirakund