Statements (A) and (C) are correct:

• Dihomo-gamma-linolenic acid (DGLA, 20:3 n-6 or 20:3 $\Delta^{8,11,14}$) has its terminal double bond at the 6th carbon counting from the methyl (omega) end ($20 - 14 = 6$), making it an essential $\omega$-6 polyunsaturated fatty acid.
• Biosynthetically, linoleic acid ($18:2\,\Delta^{9,12}$) is desaturated by $\Delta^6$-desaturase to $\gamma$-linolenic acid (GLA, $18:3\,\Delta^{6,9,12}$), which is subsequently elongated by 2 carbons via fatty acid elongase (ELOVL5) to yield DGLA (20:3).

All four molecules are classified as lipids under the broad category of prenol lipids / isoprenoids:

• Ubiquinone (Coenzyme Q): Lipid-soluble quinone containing a polyisoprenoid side chain operating within the inner mitochondrial membrane.
• Retinol (Vitamin A): Fat-soluble diterpenoid alcohol.
• Dolichol: Long-chain polyisoprenoid lipid that anchors oligosaccharides during N-linked glycoprotein synthesis in the ER membrane.
• Beta-Carotene: Lipid-soluble accessory photosynthetic tetraterpenoid pigment.

Each two-carbon elongation cycle in plastidial Type II Fatty Acid Synthase (FAS) of plants proceeds through an invariant four-step sequence:

• Condensation: Beta-ketoacyl-ACP synthase (KAS) condenses acyl-ACP with malonyl-ACP (B).
• First Reduction: Beta-ketoacyl-ACP reductase (KAR) reduces the beta-keto group using NADPH to form beta-hydroxyacyl-ACP (A).
• Dehydration: Beta-hydroxyacyl-ACP dehydratase (HAD) removes water to introduce a trans-2 double bond, forming trans-2-enoyl-ACP (C).
• Second Reduction: Enoyl-ACP reductase (ENR) reduces the double bond using NADH/NADPH to yield an elongated saturated acyl-ACP (D).

In oilseeds (e.g., castor, sunflower, soybean), neutral storage lipids predominantly in the form of triacylglycerols (TAGs) are accumulated within specialized spherical organelles termed Sphaerosomes (also known as Oleosomes, Oil bodies, or Lipid droplets). These organelles are bounded by a unique phospholipid monolayer embedded with structural proteins called oleosins, caleosins, and steroleosins that prevent coalescence of the lipid droplets. During germination, lipases associate with sphaerosomes to hydrolyze TAGs into fatty acids for glyoxysomal conversion into sucrose.