The compound has 49.3% carbon, 6.84% hydrogen, and remaining is oxygen, which is 43.86%, As these elements have relative atomic weight (roughly) of 12, 1 and 16 respectively. Their ratios in the compound is C:H:O = (49.3/12) : (6.84/1) : (43.86/16) = 4.108: 6.84: 2.74, and dividing by lowest number 2.74, we get C:H:O = 1.5: 2.5 :1 = 3:5:2, Therefore the empirical formula is C3H5O2 and molecular formula is (C3H5O2)*n , So, molecular weight (12*3 + 1* 5 + 2* 16) *n = 73n, As, vapour density is 73, Molecular weight is 2* 73 =146 and Hence, 73n = 146, implies n =2, Therefore, Molecular formula is C6H10O4. And Option D is the correct answer.