Do not be confused by absolute numbers and the need to calculate relative amounts. Look at the units used for each vitamin and nutrient. For Vitamin D, International units or micrograms, are much smaller than milligrams (mg) used for Riboflavin. But what is being asked is what is the lowest percent of target. In this case, vitamin D is the lowest vitamin in relation to the requirement. In fact, riboflavin is present at 100% of the daily requirement.