Answer: The answer is they are not closely packed
Explanation: HOPE THIS HELPS!!
D. Yep, D is the answer, alright.
Remember that any intersection of lines is a C, and that the number of hydrogens attached are the necessary to complet the 4 bonds.
1) CH3 - CH (OH) - CH (CH3) -CH3
2) CH3 - O - CH(CH3)-CH2 - CH3
I have used the parenthesis to indicate that the radical inside is in other branch, bonded by a single line -