Under appropriate reaction conditions, many organic compounds are susceptible to attack by nucleophiles. Which of the following compounds is resistant to nucleophilic attack, but readily undergoes addition reactions with electrophiles?
CH3CH2CH2I\text{CH}_3\text{CH}_2\text{CH}_2\text{I}CH3CH2CH2I
CH3CH2CHO\text{CH}_3\text{CH}_2\text{CHO}CH3CH2CHO
(CH3)2C=CHCH2CH3(\text{CH}_3)_2\text{C}=\text{CHCH}_2\text{CH}_3(CH3)2C=CHCH2CH3
CH3CH2COCl\text{CH}_3\text{CH}_2\text{COCl}CH3CH2COCl