Let's analyze the polarity and hydrogen bonding of benzene
Benzene is a no-polar molecule and does not have hydrogen bonding.
Now the most soluble solute in benzene is the one that has less polarity and does not present hydrogen bonding.
Option a) CH3OH is an alcohol and this compound is polar (short chain) and has hydrogen bonding
Option b) H2O, the water molecule is very polar and has hydrogen bonding.
Option c) CH3CH2CH2CH3 is a hydrocarbon, it is a non-polar molecule and it does not present hydrogen bonding.
The option d) H2SO4, the sulfuric acid molecule is polar and has hydrogen bonding.
Due to the above, option C) is the most soluble molecule in benzene because it is non-polar and does not present hydrogen bonding.