The mass spectrum of propan-1-ol, CH3CH2CH2OH\text{CH}_3\text{CH}_2\text{CH}_2\text{OH}CH3CH2CH2OH, is shown below.

Which ion is responsible for the peak with the greatest relative intensity?
CH3CH2+\text{CH}_3\text{CH}_2^+CH3CH2+
CH2OH+\text{CH}_2\text{OH}^+CH2OH+
CH3CH2CH2+\text{CH}_3\text{CH}_2\text{CH}_2^+CH3CH2CH2+
CH3CHOH+\text{CH}_3\text{CHOH}^+CH3CHOH+