Please answer the following question: I'm taking a test and have to guess the right answer to the question after the article. Article: Buckingham Palace has a history that dates back over 500 years and has changed hands on numerous occasions, however, much of the building that remains standing today is from the original structure built in the early 1700's. In the beginning Buckingham Palace was originally known as Buckingham House. However, in 1762 George III liked the house so much that he bought it for 28,000 and renamed it "The Queen's House". The reason for this was down to the fact that he bought the house to give to his wife Charlotte. Shortly after he did this, work soon began in order to remodel the house with the help of Sir William Chambers. This trend then continued with the accession of George IV in 1820 when he decided to reconstruct the house but he still used it for the same purpose that his father did. One of the biggest physical changes to the house occurred several years later when the king had a change of mind. It was in 1826 that King George IV set about transforming the house into what it is known today, Buckingham Palace. He did this with the help of an architect known as John Nash. The work that Nash carried out involved doubling the size of the main block through adding a new suite of rooms on the garden side facing the west. He then faced this with mellow Bath stone, which reflected the French neo-classical influence favored by George IV. Many of the rooms that Nash added still remain pretty much unchanged today. The palace as it stands today acts as not only the London residence of Her Majesty the Queen but also the administrative headquarters of the Royal Household. It is in fact one of the few working royal palaces that remain in the world today. The state rooms are extensively used by the Queen as well as members of the royal family as a way of receiving and entertaining guests on state, ceremonial and official occasions. Question: One of the biggest changes to Buckingham Palace took place in _ . Options: A: 1762 B: 1820 C: 1826 D: 1829
A:
C