Three patients in an intensive care unit are examined by a doctor. One patient has brain damage from a severe stroke. Another had a heart attack that severely damaged their heart muscle. The last patient has a disease that attacks and breaks down connective tissue in the body. All three patients have stabilized and will survive, but only one will have a full functional recovery through regeneration. Which one and why?

Once an egg cell is fertilized by sperm, the cell then, as the embryo develops, it receives nourishment and eliminates wastes by transferring substances from its blood to its mother's blood. a. becomes a fetus immediately and exits the womb b. begins to divide and implants itself in the wall of the uterus c. remains in the uterus without dividing for several months d. travels back to the ovaries until the fetus is developed