Problem: BBC experts Gianluca Vialli, Martin Keown and Jurgen Klinsmann discuss whether Italy or Spain will be victorious in the final of Euro 2012. The two countries, who played out a 1-1 draw in the group stage of the tournament, will go head to head in Kiev's Olympic Stadium on Sunday evening for the right to lift the Henri Delaunay trophy. Watch coverage of the match on BBC One, BBC One HD and the BBC Sport website from 1900 BST. Available to UK users only

Based on the paragraph above can we conclude that "Gianluca Vialli, Martin Keown and Jurgen Klinsmann are regular BBC commentators."?

A: It's impossible to say

Problem: Can I ask you about one of the limits, just focusing on the Copyright Clause and the progress of science and useful arts? In your view, does that -- is that limited to encouraging creativity by authors and inventors, or does it also include the distribution of materials that might not otherwise be distributed, like old films and so forth?

Based on the paragraph above can we conclude that "The Copyright Clause was enacted in 1950"?

A: It's impossible to say

Problem: In the two weeks since his death, police have been posted outside the Beijing home where Mr. Zhao spent his last 15 years under house arrest and where hundreds have been assembling to pay tribute. Agents have been turning many of the mourners away.

Based on the paragraph above can we conclude that "the word tribute is mentioned"?

A:
Yes