Step 1: Understanding the Problem:
The question asks to identify the oilseed that contains the highest concentration of linoleic acid (an essential omega-6 polyunsaturated fatty acid) in its oil profile among the options provided.
Step 2: Detailed Explanation:
• Linoleic Acid: Linoleic acid ($C18:2$, $\omega$-6) is an essential polyunsaturated fatty acid (PUFA) that must be acquired through diet, as the human body lacks the enzymes required to synthesize it.
• Comparison of Oil Profiles: Commercial oilseeds exhibit distinct fatty acid distributions:
• Safflower Oil (Traditional Linoleic variety): Contains the highest amount of linoleic acid among common vegetable oils, typically ranging between $70\% - 80\%$ of total fatty acids.
• Sunflower Oil: Typically contains about $55\% - 65\%$ linoleic acid (though high-oleic varieties have been bred to contain less).
• Soybean Oil: Contains around $50\% - 55\%$ linoleic acid, along with significant amounts of oleic acid ($18:1$) and linolenic acid ($18:3$).
• Mustard Oil: Characterized by high levels of erucic acid ($C22:1$) and oleic acid, with very low levels of linoleic acid (typically $< 20\%$).
Step 3: Final Answer:
Safflower oil is traditionally considered the richest commercial source of linoleic acid among the options listed, making option (C) the correct choice.