What is the healthiest cell?

A, albumin increases, plasma osmotic pressure increases, and tissue fluid decreases, which will not cause tissue edema. A is wrong;

B, albumin decreases, plasma osmotic pressure decreases, antidiuretic hormone secretion decreases, urine volume increases, B is correct;

C, albumin has no ability to transport oxygen, and C is wrong;

D, the main function of albumin is to maintain plasma osmotic pressure, not to participate in immune regulation, D error.

Therefore, choose: B.