With the Federal Trade Commission (FTC) taking a scalpel to the pharmacy benefit managers (PBMs) of UnitedHealth Group Inc UNH, CVS Health Corp CVS and Cigna Group CI, investors are left wondering which health giant can best weather the storm.The FTC's lawsuit, targeting these companies for allegedly inflating insulin prices, could have a major ripple effect across the healthcare industry—and that means stock volatility. So, which stock looks healthier?UnitedHealth Group: Big & Bold, But Under The Microscop ...