HMRC stands for Her Majesty's Revenue and Customs, which was the correct name during Queen Elizabeth II's reign. Option B is correct because it uses 'Her Majesty's' (the standard feminine form). His Majesty's would only apply under a male monarch, and 'Hi' is clearly a typo. After King Charles III ascended the throne in 2022, it technically became His Majesty's, but Her Majesty's remained the official name in common usage during the Queen's reign.