Which of the following is a dietary source of alpha-linoleic acid?

Alpha-linoleic acid (ALA) is a type of omega-3 fatty acid that is mainly found in plant-based oils. The primary dietary sources of ALA include various plant oils, with vegetable oils such as flaxseed oil, canola oil, and walnut oil being among the richest sources. Unlike animal-based products such as eggs, milk, and chicken, which contain different types of fats, vegetable oils are specifically notable for their high ALA content. This is why vegetable oil is the correct answer, as it serves as a significant dietary source of alpha-linoleic acid and supports the intake of essential omega-3 fatty acids.