Correct Answer - D
`CO_2` is linear, `CH_4` is tetrahedral with zero lone pair, `NH_3` is tetrahedral with one lone pair, while `H_2O` is tetrahedral with two lone pairs. Thus, the order of bond angle is `CO_2(180^@)gtCH_4(109.50^@)gtNH_3(107^@)gtH_2O(104.5^@)`