Answer: The “Developer Options” menu item on 4.2.* is hidden.
1. Goto Settings -> About Phone.
2. Goto “Build Number” at the end of the Scroll list.
3. Tap on “Build Number” repeatedly (7 times). On your third tap you should see message indicating that you only have 4 more taps to go to ‘become a developer’.
4. Continue: 4 more taps.
5. Hooray, you are now a ‘Developer’, go back to the Setting page.
6. You should see Developer Option menu item in your setting list now.
7. Open Developer Options and check USB debugging > Ok