This is apoptosis. in reference to sunburn, this is when cells die in order to protect you and your skin from damaged skin DNA (possibly cancer causing).
The substances that protect against oxidative stress and the resultant tissue damage at the cellular level is, option B. Antioxidants. Oxidation can cause imbalance in the body. Antioxidants are used to counteract the damage produced by free radicals. Good natural sources of antioxidants include fruits and vegetables.
The structure of the lipid bilayer allows small, uncharged substances such as oxygen and carbon dioxide, and hydrophobic molecules such as lipids, to pass through the cell membrane, down their concentration gradient, by simple diffusion.
B. the bond forms when electrons are shared
