Quiz statistics in 2.7+ not clear which link to click to drill down for random questions

Steps to reproduce:

1. Create a category of question containing about 20 questions.
2. Create a quiz, and add 11 random questions picked from that category.
3. Make attempts as a number different students, until you have seen more than 10 of the randomly selected quetsions from the category of 20.
4. Go to Quiz administration -> Results -> Statistics

You should see 11 rows of the table, one for each 'slot' where a random question was added to the quiz, and then, under the last slot, three rows summarising the best, worse and median stats from amoung the questions picked from that category.

What is not obvious is that if you click on the link in row 11 (the last one above the three-row break-down) you get more information about all 20 questions that were picked from the random category. The first 10 rows have identical-looking links that go do a different page of more detailed information.

Clearly we need to chagne the appearance and wording of the links, to make it clearer what links go where, so that people can find the information that is there.

Note that 10 is a magic number here. When there are 10 or fewer rows in the full data, it is shown inline on the front page of the report.