The correct answer is: C. ground the framework
Static electricity is a build-up of electrical charge on an object. It can be caused by friction, such as when you rub your feet on the carpet. When you touch something, the static electricity can discharge, causing a spark.
Static electricity can be a problem in machinery because it can cause sparks that can ignite flammable materials. To remove static electricity from machinery, you can ground the framework. This means connecting the framework to a ground wire, which will allow the static electricity to flow away safely.
Option A is incorrect because insulated cabins will not remove static electricity. In fact, they may make the problem worse by insulating the machinery from the ground.
Option B is incorrect because insulating the machinery will not remove static electricity. It will only prevent the static electricity from discharging, which could make the problem worse.
Option D is incorrect because humidifying the surroundings will not remove static electricity. It may help to reduce the amount of static electricity that builds up, but it will not eliminate it.
In conclusion, the correct answer is: C. ground the framework. This is the most effective way to remove static electricity from machinery.