Which method is used to remove an item from a list by its value?

The method used to remove an item from a list by its value is list.remove(value). This method searches the list for the first occurrence of the specified value and removes it. If the value is not found, a ValueError is raised, alerting the user that the item to be removed does not exist in the list. This function is particularly useful when you know the specific item you want to remove rather than its index.

In contrast to the correct answer, the other methods do not serve this purpose. The list.pop() method is designed to remove an item at a specified index and return it, defaulting to the last item if no index is given. list.delete() is not a valid list method in Python, as there isn’t a delete method for lists. Lastly, list.discard() is typically associated with sets, not lists, and is used for removing elements from a set without raising an error if the value is not present. Thus, list.remove(value) is the appropriate choice for removing an item from a list by its value.