What are the variants of Tata Nano?

Tata Nano varaints are immensely efficient and worth buying. There are a total of 12 Tata Nano variants available currently. They are as follows: -    1) Tata Nano STD BS III 2) Tata Nano STD  3) Tata Nano 2013 STD  4) Tata Nano Cx BSIII 5) Tata Nano Cx 6) Tata Nano 2013 CX 7) Tata Nano LX BSIII 8) Tata Nano LX 9) Tata Nano 2013 LX 10) Tata Nano Twist XT 11) Tata Nano CNG CX 12) Tata Nano CNG LX