In order to find the percent composition for Nitrogen in NH4NO3, we will need to work with all the masses from this compound, so let's list them below:
NH4NO3 = 80.04 g/mol
N = 14 grams, but we have 2 nitrogens, therefore = 28 grams
H = 1 gram, 4 Hydrogens = 4 grams
O = 16 grams, 3 Oxygens = 48 grams
Now we take the total mass of the compound as 100% and check how much it will be made by Nitrogen:
80.04 g = 100%
28 g = x %
x = 34.98%, which we can round up to 35% therefore the answer will be letter E
