The difference between the formula you just wrote out and the molecular formula of compound E is one atom. That atom is part of the functional group that also acounts for the singlet at 5.4 ppm in the 1H NMR spectrum. What is the name of that functional group?

Hydroxyl group -OH

Explanation:

This is because the Hydroxyl group has a single atom which can indicate a singlet on the proton Nmr analysis and the value for -OH is around 4 - 5 ppm as well making the unknown functional group to be likely Hydroxyl group

it would be b. 6co2 + 6h2o --> c6h12o6 + 6o2