A nitrogenous compound is treated with `HNO_(2)` and the product so formed is further treated with NaOH solutoin which produces blue colouration. The nitrogenous compound is:
A. `CH_(3)CH_(2)NH_(2)`
B. `CH_(3)CH_(2)NO_(2)`
C. `CH_(3)CHONO`
D. `CH_(3)underset(CH_(3))underset(|)(CH)NO_(2)`