Can someone explain what's happening here?

Question

So this is the final question of the chapter "Working with Strings":

Fill in the blanks to assign the last character of the string to the x variable:

string s = "Hello";
char x;
x = _ [s.Length-1 _;

I get that you have to close the brackets and I guessed that the other space was "s" . But i literally guessed it. That last line of code is messing me up. Can someone explain to me why this code ( x = s [ s.Length-1]; ) is correct? Thanks and sorry for the mediocre english.

Answer 1

x =s[s.Length - 1];
This is the easy answer

Answer 2

Thank you! I was at a loss and now i feel really dumb. That was a really nice explanation.