Correct Answer - D
Equation for combustion of alkanes is as follows
`C _n H _( 2 n + 2 ) + ((3n + 1 )/( 2 )) O_ 2 to nCO _ 2 + ( n + 1 ) H _ 2O + ` Heat
Greater the value of n greater will be the heat produced. Therefore, on combustion butane gives maximum energy.
