Read the passage carefully and choose the correct answer.
There is very little documentation about the origins of water polo. It is known, however, that the sport originated in the rivers and lakes of mid-19th century England as an aquatic version of rugby. Early games used an inflated rubber ball that came from India known as a "pulu" (the single Indian word for all "balls"). Pronounced "polo" by the English, both the game and the ball became known as "water polo." To attract more spectators to swimming exhibitions, the London Swimming Association designed a set of water polo rules for indoor swimming pools in 1870. At first, players scored by planting the ball on the end of the pool with both hands. A favorite trick of the players was to place the five-to-nine inch rubber ball inside their swimming suit and dive under the murky water, they would then appear again as close to the goal as possible. The introduction of the rules by Scottish players changed the nature of water polo. It became a game that emphasized swimming, speed and passing. Scottish rules moved from a rugby variant to a soccer style of play. Goals became a cage of 10x 3 feet and a goal could be scored by being thrown. Players could only be tackled when they "held" the ball and the ball could no longer be taken under water. The small rubber ball was replaced by a leather soccer ball. If the player came up too near the goal, he was promptly jumped on by the goalie, who was permitted to stand on the pool deck. Games were often nothing more than gang fights in the water as players ignored the ball, preferring underwater wrestling matches that usually ended with one man floating to the surface unconscious. Water polo was first played in the USA in 1888. The game featured the old rugby style of play which resembled American football in the water. "American style" water polo became very popular and by the late 1890's was played in such venues as Madison Square Garden and Boston's Mechanics Hall, attracting 14,000 spectators to national championship games.
Water polo became popular in America in _______.
the middle of the 19th century in 1870 in 1888 by the late 1890's