The correct option is B A game becomes really interesting if one knows, beforehand, how it is going to end.
We need to choose the option that does NOT hold true for the given passage. Hence, Option B is chosen; it is a false statement as proved by the line: "Games lose their zest... if the result is a foregone conclusion." (foregone conclusion means 'a result that can be predicted easily)
Option A is not chosen because it is true. This is proved by the line: "Life indeed would be dull if there were no difficulties."
Option B is not chosen because the line holds true and "Games lose their zest if there is no real struggle..." proves it.
Option D is also not chosen; it is true, proved by the line: "Both the winner and the loser enjoy a game most when it is closely contested to the end."