MARKET WATCH: “The public option, whether we have it or we don’t have it, is not the entirety of health-care reform,” Obama said on Saturday in Grand Junction, Colo. “This is just one sliver of it.” Bucking a bearish Monday trend in the broader stock market, shares of health-insurance companies including UnitedHealth Group Inc.  (UNH 28.95, +0.47, +1.65%) and Aetna Inc. (AET 29.54, -0.09, -0.31%) rose after the comments by Obama as well as members of his administration over the weekend. Health insurers have fought a public plan. Republicans, long opposed to a public plan, seized on comments made Sunday […]