What syntax is used to convert a number into a string in Python?

The syntax used to convert a number into a string in Python is indeed represented by the str(number) function. This built-in function takes a number as an argument and returns its string representation.

For example, if you have a number like 42, using str(42) will yield the string '42'. This method is straightforward and widely used when there's a need to concatenate numbers with strings or when you want to ensure that a numeric value is treated as a string in operations.

The other options do not provide the correct method for this conversion. The method number.toString() resembles JavaScript syntax for converting numbers to strings and is not valid in Python. The function float(number) is used to convert a value into a floating-point number, not a string. Lastly, number.str() is also incorrect as it does not follow Python's syntax for conversion and would raise an error since str is not a method associated with the number data type in Python. Thus, the function str(number) is the appropriate and valid way to perform this conversion.