The fact that the two great athletes

Nice analysis, aerofred!

We can eliminate A, C, and E because the subject "fact" is singular, so we need to pair it with a singular verb to create agreement between the noun and the verb. This is easier to see if we take out the extra descriptive information in the sentence:

The fact that the two great athletes will face each other in each of the season’s three largest events - the Olympics, the World Championships, and the European Open - give the sport a rare tension, which is certain to create increased interest.

The fact ... give the sport a rare tension ...

The difference between B and D is tense. B indicates that the athletes will face each other, and this gives the sport tension, which will create interest. This makes sense: the anticipation of these athletes facing each other IN THE FUTURE gives the sport tension NOW and will create interest IN THE FUTURE. D on the other have indicates that the athletes will have faced each other, and this will give the sport tension, which will create interest. The use of "will have faced" in D indicates that when the sport will have more tension/create more interest AFTER the athletes have already faced each other. This doesn't make much sense — if the sports events are already over, how will the sport be tense or interesting?

So we select B as the correct answer.