Because humans have five senses: feel, see, taste, hear, and smell. When you step on a nail you basically going to feel it and you brain can sense that and it can trigger nerves which can cause pain.
The spread of cancer from its point of origin is called metastasic cancer.
Metastasic cancer can also be identified as metastasized cancer as well. Most of the types of metastasic cancer cannot be cured with treatment, unlike others which can.
I would be dead any way so why worry about it go spend time with you family and ignore it family will always be there for you not some weird drugs said to cure you but ends up being the thing to kill you.
The correct answer from the list above would be "the bending of the arm". please rate and thanks :)