An engine’s iron cylinder has to be inserted into a section of aluminium. The iron cylinder’s outside diameter $M$ is a little greater than the diameter $N$ of the hole in the aluminium. What is the most suitable way to make the cylinder fit into the aluminium?
- ACool the aluminium and cool the iron.
- BCool the aluminium and heat the iron.
- CHeat the aluminium and cool the iron.
- DHeat the aluminium and heat the iron.