Re-answering this to explain further what explain As I said, A uses past perfect which expresses regret or to say something had happened before something else Ex. "It turns out, Britain had won an olympic gold medal before the olympics even started" or "If only britain had won an olympic gold medal..." B uses present simple, which is used to express facts, or planned events. Since newspapers are (supposed to be) reporting facts, they use the present simple. C uses the past simple tense, this is used to describe past actions at a particular time, past events that have stopped, and hypothetical situations (now or in the future). Newspapers would use this because even though it doesn't specifically state the particular time, it's obvious. D uses the present perfect tense, which is used to express and action in the past (that is still happening now), or something that has recently finished, something in the past with no time frame. A newspaper would use this during the olympic games because the medal has recently been won (the winning of that particular medal has recently finished).

All except A would be acceptable in this context. Although the sentence "Britain had won another Olympic gold medal" does make sense and is grammatically correct, it wouldn't be correct to use it in this particular context. A uses the past perfect tense which is used to express regret or to talk about something that happened before something else. So you wouldn't use it just to say they "had won" a medal. Generally this tense isn't used in headlines. The other three are correct, though B and D are used most often and definitely sound better in this context!

A is wrong for me, but the others are possible. B is best because of that fact-beyond-time quality of a newscast. Written headlines in the newspaper also use simple present because it's shorter and saves space. "Headline" for a spoken "top story" sounds like non-American usage to my ear, but the point is still valid. The three questions you have posted now seem to be testing the same thing.

Yes - all would be acceptable, from a purely English point of view. But they have quite deliberately 'set the scene' - by mentioning that it is a news headline. Newspaper headlines are always (a) brief, and (b) sensational. So, the answer will be short, and 'catchy'. B.