Correct Answer: Phospholipid

Solution : The correct option is - Phospholipid

The plasma membrane in eukaryotic cells is primarily composed of lipids and proteins. It has a phospholipid bilayer structure which means it consists of two layers of phospholipid molecules arranged with their hydrophobic tails facing inward and their hydrophilic heads facing outward. This arrangement creates a semi-permeable barrier that separates the internal and external environments of the cell.