Who was the son of Mary Stuart and succeeded Elizabeth I as the King of England?

The son of Mary Stuart, also known as Mary, Queen of Scots, who succeeded Elizabeth I as the King of England was James I. Mary Stuart's marriage to Henry Stuart, Lord Darnley, produced James, who became King of Scotland as James VI. With Elizabeth I's death in 1603 and the end of the Tudor line, James succeeded her as the first monarch of both England and Scotland, initiating the Stuart dynasty in England. His reign marked the beginning of a new era, and he is well-known for commissioning the King James Version of the Bible, which has had a lasting impact on English literature and Christianity.

The other choices are notable figures in British history but do not fit the criteria specified in the question. Henry VIII was the father of Elizabeth I and renowned for his six marriages and the English Reformation. Charles I was the son of James I and became king after him, but he was not the direct successor of Elizabeth I. George I was a later monarch, coming to the throne in the early 18th century, much after both Elizabeth I and James I. Hence, James I is the correct answer as he directly followed Elizabeth and was the son of Mary Stuart.