Answer:
The answer to your question is: letter E
Explanation:
Normally, the correct order of boiling points is:
           Alcohols > Ketones > Ether > Alkane
Then
A. n-butane < 1-butanol < diethyl ether < 2-butanone
B. n-butane < 2-butanone < diethyl ether < 1-butanol
C. 2-butanone < n-butane < diethyl ether < 1-butanol
D. n-butane < diethyl ether < 1-butanol < 2-butanone
E. n-butane < diethyl ether < 2-butanone < 1-butanol
   (- 1°C)   <   34.6°C     <  79.64°C    <  117.7°C