The decreasing order of basic strength in
`{:(C_(6)H_(5)NH_(2)",",(C_(6)H_(5))_(2)NH",",CH_(3)NH_(2)",",NH_(3)),(" (I)"," (II)"," (III)","(IV)"):}`

Options

A. `IV gt III gt II gt I`
B. `I gt II gt III gt IV`
C. `III gt IV gt I gt II`
D. `II gt I gt III gt IV`

Explanation

To determine the decreasing order of basic strength among the compounds given, we need to analyze the structure and effects of substituents on the nitrogen atom in each compound. The compounds in question are:

1. Aniline (C6H5NH2) - (I)
2. Diphenylamine ((C6H5)2NH) - (II)
3. Methylamine (CH3NH2) - (III)
4. Ammonia (NH3) - (IV)

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