Answer: Dip tube. This tube, located at the top of the tank, serves as the entry point for water as it flows into the tank. The water then travels to the bottom of the tank, to the area known as the combustion chamber, where the heating process begins.
Explanation: Thats what the internet says, and the internet is almost always right, hope you get it right.
A microscope is to see smaller things that you can’t see and it is a really good tool.
The answer for this question is C.