The correct answer is: D. U.S. Open
The U.S. Open had the highest total prize money (in terms of US Dollars) in the year 2014. The total prize money for the 2014 U.S. Open was $42.3 million, which was an increase of 10% from the previous year. The men’s and women’s singles champions each received $3.6 million, which was an increase of 10% from the previous year.
The Australian Open had a total prize money of $33.2 million in 2014, which was an increase of 10% from the previous year. The men’s and women’s singles champions each received $2.8 million, which was an increase of 10% from the previous year.
The French Open had a total prize money of $28.6 million in 2014, which was an increase of 10% from the previous year. The men’s and women’s singles champions each received $2.2 million, which was an increase of 10% from the previous year.
Wimbledon had a total prize money of £28.7 million in 2014, which was an increase of 10% from the previous year. The men’s and women’s singles champions each received £1.7 million, which was an increase of 10% from the previous year.
The U.S. Open has had the highest total prize money of the four Grand Slam tournaments since 2007. The increase in prize money at the U.S. Open has been due to a number of factors, including the increasing popularity of tennis in the United States, the increasing value of the U.S. dollar, and the increasing number of corporate sponsors.