When inspecting the exhaust system, which of the following should not cause concern?

When inspecting a vehicle's exhaust system, be alert to a number of potential problems, including loose, broken, or missing exhaust pipes, mufflers, tailpipes, or vertical stacks; loose, broken, or missing mounting brackets, clamps, bolts, or nuts; exhaust system parts rubbing against fuel system parts, tires, or other moving parts of the vehicle; and exhaust system parts that are leaking.