You will be given a definition of a task first, then an example. Follow the example to solve a new instance of the task.
In this task, you will be presented with a passage and have to answer a question based on your understanding of the events inferred from the passage. Among the entities, try to find the best entity that is most likely to fill in "_" and classify the answers based on options.

For four years we have waited expectantly for the pitter patter of tiny paws. Soon, that wait could finally be over. Tian Tian, the UK's only female giant panda, has conceived and could give birth to a cub as early as August. However Edinburgh Zoo, where the pandas live, have warned people 'not to get too excited' as the process is 'extremely complex'. Moreover, on the two previous occasions keepers inseminated Tian Tian - whose name means 'Sweetie' - she has failed to produce a panda cub. She was artificially inseminated again in March this year, but keepers at the zoo say implantation - when a fertilised egg attaches to the uterus - has not yet occurred.Tian Tian has conceived and could give birth to a cub as early as AugustShe has been inseminated twice before but so far failed to produce a cubTian Tian and Yang Guang arrived in 2011 from China to great fanfareOn loan at £600k a year, became first giant pandas to live in UK for 17 years 
 Questions:Under the terms of the agreement any cubs will return to _ at the age of two, the age at which they would normally leave their mother in the wild. (A) Tian Tian (B) UK (C) Edinburgh Zoo (D) Sweetie (E) Yang Guang (F) China
Solution: (F)
Why? This is a good example. Based on the passage, any cubs will return to China at the age of two

New input: London (CNN) The wife of an American professor was killed and five others injured in a knife attack in central London's Russell Square in what police Thursday called a "spontaneous" assault. London Metropolitan police identified her as Darlene Horton, 64. She was married to a Florida State University professor, the university said. Richard Wagner, a professor of psychology, and Horton were in London, where he taught a summer session for the university. The couple had planned to return to Tallahassee on Thursday. The stabbings late Wednesday night rattled the city popular with tourists and came just hours after authorities announced an increased police presence there following recent terror attacks across Europe.Victim stabbed to death was American woman in her 60s, police say"We have found no evidence of radicalization," official says 
 Questions:"I studied in _, so I used to come here frequently. (A) London (B) CNN (C) American (D) Russell Square (E) Darlene Horton (F) Florida State University (G) Richard Wagner (H) Horton (I) Tallahassee (J) Europe
Solution:
(A)