Which of the following functions does not throw an error?

The correct answer is Option B: ord(' ').
The ord() function in Python is used to get the Unicode code point of a character. When you pass a single character as an argument to the ord() function, it returns the Unicode code point of that character. In this case, passing a space character (' ') to the ord() function will not throw an error, as it represents a valid Unicode character. It returns the Unicode code point for the space character, which is 32.

The other options will result in errors:
Option A: ord() without any argument throws a TypeError because it requires exactly one argument.
Option C: ord(") throws a TypeError because it's missing the character argument.
Option D: ord("") throws a TypeError because it's passing an empty string as an argument, which is invalid.