Why Would a Patient on Mechanical Ventilation Have a Rapid

Why would a patient on mechanical ventilation have a rapid weight gain?

A) Lack of motility slows the metabolic rate.
B) Positive pressure ventilation decreases venous return, decreases blood pressure, and stimulates renin-angiotensin-aldosterone.
C) Positive pressure ventilation forces fluid into the third space.
D) Positive pressure ventilation increases venous return and stimulates release of antidiuretic hormone.