PCEP Control Flow, Loops, Lists and Logic Practice Question

Which two of the following list methods modify the original list in place? (Choose two.)

⚠ Common exam trap

Python Institute often tests the distinction between methods that mutate the list in place (like `sort()`) and functions that return a new list (like `sorted()`), as well as the fact that `count()` and `copy()` are non-mutating, to see if candidates confuse method behavior with function behavior.

Answer choices

Why each option matters

Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.

Correct answer & explanation

✓

sort()

A is correct because the `sort()` method sorts the list in place, meaning it modifies the original list object without creating a new one. D is correct because `append()` adds an element to the end of the list, directly mutating the original list.

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

✓
sort()
Why this is correct
Sorts the list in place.
✗
count()
Why it's wrong here
Returns count of elements, does not modify.
✗
sorted()
Why it's wrong here
Returns a new sorted list, does not modify original.
✓
append()
Why this is correct
Modifies the list by adding an element.
✗
copy()
Why it's wrong here
Returns a shallow copy, does not modify original.

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PCEP Control Flow, Loops, Lists and Logic Practice Question

Why each option matters

Option-by-option breakdown

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