Which of the following best describes functions in Python?

Functions in Python are best described as reusable blocks of code. This means that once a function is defined, it can be used multiple times throughout a program without needing to rewrite the same code. Functions help in organizing code into logical sections, making programs easier to read, maintain, and debug.

The ability to pass arguments to functions and return values also enhances their usefulness, allowing for dynamic behavior based on the input provided. This feature significantly reduces redundancy in code, promoting better programming practices.

Other options, such as global variables, data types, and conditional statements, serve different purposes in programming. Global variables are accessible throughout the entire program but do not encapsulate functionality like functions do. Data types classify the nature of data (like integers, strings, and lists) rather than providing reusable behavior. Conditional statements, such as if-else, control the flow of execution based on certain conditions but do not encapsulate blocks of code in a reusable manner like functions.