Question: Alain Fossoul played this position whose primary role is to prevent the opposing team from what

Context paragraphs:
American football: American football, referred to as football in the United States and Canada, and also known as "gridiron football" or simply "gridiron", is a sport played by two teams of eleven players on a rectangular field with goalposts at each end.  The offense, the team with control of the oval-shaped football, attempts to advance down the field by running with or passing the ball, while the team without control of the ball, the defense, aims to stop their advance and take control of the ball for themselves.  The offense must advance at least ten yards in four downs, or plays, or else they turn over the football to the opposing team; if they succeed, they are given a new set of four downs.  Points are primarily scored by advancing the ball into the opposing team's end zone for a touchdown or kicking the ball through the opponent's goalposts for a field goal.  The team with the most points at the end of a game wins.

Professional fraternities and sororities: Professional fraternities, in the North American fraternity system, are organizations whose primary purpose is to promote the interests of a particular profession and whose membership is restricted to students in that particular field of professional education or study.  This may be contrasted with service fraternities and sororities, whose primary purpose is community service, and general or social fraternities and sororities, whose primary purposes are generally aimed towards some other aspect, such as the development of character, friendship, leadership, or literary ability.

Offense (sports): In sports, offense (US) or offence (Can. ) (see spelling differences; pronounced with first-syllable stress; from Latin "offensus"), also known as attack, is the action of attacking or engaging an opposing team with the objective of scoring points or goals.  The term may refer to the tactics involved in offense, or a sub-team whose primary responsibility is offense.

Polo: Polo (Persian: چوگان "chogān") is a team sport played on horseback.  The objective is to score goals against an opposing team.  Players score by driving a small white plastic or wooden ball into the opposing team's goal using a long-handled mallet.  The traditional sport of polo is played on a grass field up to 300 by .  Each polo team consists of four riders and their mounts.

Goalkeeper (association football): Goalkeeper, often shortened to keeper or goalie, is one of the major positions of association football.  It is the most specialised position in the sport.  The goalkeeper's primary role is to prevent the opposing team from successfully moving the ball over the defended goal-line (between the posts and under the crossbar).  This is accomplished by the goalkeeper moving into the path of the ball and either catching it or directing it away from the vicinity of the goal line.  Within the penalty area goalkeepers are able to use their hands, making them (outside of throw-ins) the only players on the field permitted to handle the ball.  The only time when a goalkeeper is not allowed to use their hands inside their box is when a field player of their own team does a direct pass.  The most common way to know that it is a direct pass, and not an indirect pass, is when the field player has control of the ball.  Goalkeepers are allowed to pick up the ball during an indirect hit from a teammate (headers, chest, knee thigh, and when the ball bounces off the player).  Goalkeepers usually perform goal kicks, and also give commands to their defense during corner kicks, direct and indirect free kicks, and marking.  Goalkeepers play an important role in directing on field strategy as they have an unrestricted view of the entire pitch, giving them a unique perspective on play development.  If an attacker on the opposing team obstructs the keeper from catching or saving the ball, for example, in a corner, it will normally be a free kick.

Defender (association football): In the sport of association football, a defender is an outfield player whose primary role is to prevent the opposing team from scoring goals.

Street hockey: Street hockey (also known as dek hockey, ball hockey, and in some parts of Canada road hockey) is a variation of the sport of ice hockey where the game is played outdoors on foot, or with inline or roller skates using a ball or puck.  Both ball and puck are typically designed to be played on non-ice surfaces.  The object of the game is to score more goals than the opposing team by shooting the ball or puck into the opposing team's net.  Street hockey in pickup form is generally played under the following guidelines, since there are no "official rules" for local pickup hockey:

Dota 2: Dota 2 is a free-to-play multiplayer online battle arena (MOBA) video game developed and published by Valve Corporation.  The game is the stand-alone sequel to "Defense of the Ancients" ("DotA"), which was a community-created mod for Blizzard Entertainment's "" and its expansion pack, "".  "Dota 2" is played in matches between two teams of five players, with each team occupying and defending their own separate base on the map.  Each of the ten players independently controls a powerful character, known as a "hero", who all have unique abilities and differing styles of play.  During a match, the player collects experience points and items for their heroes in order to successfully fight the opposing team's heroes, who are doing the same.  A team wins by being the first to destroy a large structure located in the opposing team's base, called the "Ancient", which is guarded by defensive towers.

Alain Fossoul: Alain Fossoul (31 December 1928 – 9 May 2012) was a Belgian footballer who played as a defender.

Defenceman: Defence (defense in the USA) in ice hockey is a player position whose primary responsibility is to prevent the opposing team from scoring.  They are often referred to as defencemen, defencewomen or defenceplayers, D, D-men or blueliners (the latter a reference to the blue line in ice hockey which represents the boundary of the offensive zone; defencemen generally position themselves along the line to keep the puck in the zone).  They were once called cover-point.  A good defenceman is both strong in defensive and offensive play and for defenceman pairing also need to be good at defending and attacking.

Supporting paragraphs: Alain Fossoul Defender (association football)
Answer: scoring goals