Which among the following pairs of Vitamins is stored in our body relatively for longer duration?

Vitamins are classified into two categories: water-soluble vitamins and fat-soluble vitamins. Water-soluble vitamins (such as B-complex vitamins including thiamine/$$B_1$$, and vitamin C/ascorbic acid) are not stored in the body for long periods and are readily excreted through urine. Fat-soluble vitamins (vitamins A, D, E, and K) are stored in the liver and fatty tissues of the body for relatively longer durations.

Now let us examine the options. Option (1) contains thiamine (a water-soluble vitamin) and vitamin A (fat-soluble), so this pair does not qualify since thiamine is not stored for long. Option (3) contains thiamine and ascorbic acid, both water-soluble, so neither is stored for long. Option (4) contains ascorbic acid (water-soluble) and vitamin D (fat-soluble), so this pair also does not fully qualify.

Option (2) contains vitamins A and D, both of which are fat-soluble vitamins that are stored in the body for relatively longer duration.

Hence, the correct answer is option (2).