Which Android platform should i develop my unity game for?

I have made a game and want to build it for android phones… but which android platform should i choose? Should i choose the latest one? Will it run on phones with lower versions too? Please help me out here. I am new to this process. Thanks!

This graph shows the most common SDK installed on Android phones and tablets used by AppBrain users as of March 28, 2014.

http://www.appbrain.com/stats/top-android-sdk-versions

According to it, I will start to build my games from 2.3 version (16.6 % of all devices)

Depending of what target you want. If you want to develop for modern mobiles then go from 4.1-4.3 (Jelly Bean), else from 2.3.

Hence, if you build it for Kit Kat, the devices with Jelly Bean won’t be able to run your game. But if you build for 2.3 all the devices with 2.3 and higher will be able to run your game.