Which of the following actions is considered dangerous play?

Impediment of an opponent is considered dangerous play because it often involves intentionally obstructing an opponent in a way that could increase the risk of injury. This action can disrupt the flow of play while also leaving a player vulnerable to a collision or fall, particularly in situations where they are trying to maintain possession of the ball or make a play. The act of impeding does not require physical contact, but the potential for danger stems from compromising the safety of other players on the field.

Tripping, striking, and holding, while they may lead to potentially dangerous situations, are more straightforward fouls leading to free kicks or other sanctions rather than specifically categorized as dangerous play under the laws of soccer. Dangerous play emphasizes actions that compromise player safety, and impeding is often an indirect way of creating such risks without the immediate physicality of a foul.