POLYUNSATURATED FATTYACEDS Polyunsaturated fatty acids have more than one double bond. According to the position of first double bond they or divided into1)   n-3 fatty acids or ω-3 fatty acids or omega-3 fatty acidsThis are long-chain polyunsaturated fatty acids, with first double bond beginning at the third carbon atom (when counting form the methyl end of fatty acid). Example are α- linolenic acid, Timnodonic (Eicosapentaenoic) acid, cervonic (Docosahexaenoic acid). Rich sources → wheat, bajara, mustard, fish, lobia, rajmah, black gram, soybean, green leafy vegetables.2)   n-6 or ω-6 or omega-6 fatty acidsFirst double bond begins at the 6th carbon atom. Examples Linoleic acid, Arachidonic acid, γ-linolenic acid.Rich sources → Groundnut oil & corn oilComing back to questionBoth groundnut oil and corn oil are devoid of (0-3 fatty acids. However, corn oil has trace amount of w-3 fatty acids. So, best answer of this question is groundnut oil.Following information have been added in 21st/e of ParkThe WHO/FAO expert Group on diet, nutrition and prevention of chronic diseases endorse that qualitative composition of fats in the diet has a significant role to play in modifying risk factors for CHD and set the following ranges for population nutrient goals (% of energy) : -Total fat intake, 20-30% of total energy intake (at least 20% energy is consistent with good health). Saturated fatty acids, less than 10% of total energy intake. PUFAs, 6-10% of total energy intake (minimum of 6%). ω-6 should be about 5-8% and ω-3 should be about 1-2%. Trans fatty acids should be less than I% of total energy intake. Cholesterol should be less than 300 mg a day.It is worth noting here that above values are for prevention of CHD. However, minimum intake levels for essential fatty acids to prevent deficiency symptoms are estimated to be 2.5% of total intake for lenoleic acid and 0.5% for Lenolenic acid (ALA).