In a cell membrane, how do hydrophilic and hydrophobic interactions contribute to its structure?

• A. Hydrophilic tails face outward and hydrophobic heads face inward, forming a bilayer.
• B. Hydrophilic heads face outward and hydrophobic tails face inward, forming a bilayer.
• C. Both hydrophilic and hydrophobic parts face outward, forming a single layer.
• D. Both hydrophilic and hydrophobic parts face inward, forming a single layer.

Answer: (B)