Which of the following contacts may be confirmed through the Logbook of The World (LoTW)?

The Logbook of The World (LoTW) is an online database maintained by the ARRL for verifying amateur radio contacts digitally. It is highly versatile and accepts digitally signed logs for virtually any valid two-way amateur radio contact, completely eliminating the need for physical QSL cards. Because the system simply cross-matches uploaded logs from participating stations, it supports a wide variety of awards and contact types. This includes special event stations within the US, international DX contacts between a US and non-US station, and domestic contacts used for awards like Worked All States (WAS). Since LoTW securely validates all these types of QSOs as long as both operators upload their matching logs, every listed option represents a valid use of the system.