“Scenario 2: One day you make a phone call to him and
he said only he and his two children are at home. You
hear some boy's voice among backgroudn noise.”
难道这不是说这boy's voice among backgroudn noise 来自“his two children are at home ”？
否则，给你INFO有什么用？
退一步讲，如果认为这boy's voice among backgroudn noise 是来自“his two children are at home ”，那么1/3是正确的答案，对吧。
http://www.xys.org/forum/db/3/188/41.html