Let’s track it. Remove method accepts index to discard the value.
For i=0, it is even number value at index 0 removed from list updated list values: acct1, acct2, acct3, acct4. Please remember after removal operation; indexes are recalculated based on the new order of list.
For i=1, it is not even number; Nothing happens.
For i=2, it is even number; value at index 2 will be removed from list According to new order, acct3 is at index 2, so it will be removed. Updated list: acct1, acct2, acct4
For i=3, it is not even number; nothing happens
For i=4, it is even; but the new list contains only 3 elements, and a statement will try to remove