Question

The richest source of Vitamin D is—

• A. Cod liver oil
• B. Spinach
• C. Milk
• D. Cheese

Hint:

Cod liver oil is fat extracted from fish liver, where fat soluble vitamins like D are stored in high amounts.

Answer 1

The Correct Option is A

Step 1: Recall what Vitamin D does and where it comes from.
Vitamin D helps the body absorb calcium and phosphorus, which keeps bones and teeth strong. Unlike most vitamins, very little of it comes from plant foods. The main natural sources are sunlight acting on the skin and a small number of animal based foods, chiefly fish liver oils, egg yolk, and fatty fish.

Step 2: Compare the amount of Vitamin D in each option.
Cod liver oil is oil taken from the liver of the cod fish. Fish liver is where the fish stores fat soluble vitamins, so cod liver oil is extremely concentrated in both Vitamin D and Vitamin A. A single spoon of it can supply many times the daily requirement of Vitamin D, making it the richest known dietary source.

Step 3: Check why the other options are poor sources.
Spinach is a leafy green vegetable. Plants do not make Vitamin D, so spinach has almost none. It is rich in iron and Vitamin K instead.
Milk contains only a small, often fortified, amount of Vitamin D. Dairies frequently add Vitamin D to milk artificially precisely because milk on its own is a weak natural source.
Cheese is made from milk, so it carries only trace amounts of Vitamin D as well, far less than cod liver oil.

Step 4: Final answer.
Among the four choices, cod liver oil has by far the highest concentration of Vitamin D.
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