Definition: 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. Try to find the best answer that is most likely to fill in "_". Note that the URLs in the text have been replaced with [Link].
Input: The murder of a woman at a popular San Francisco pier allegedly by an illegal immigrant could have been avoided, federal immigration officials said Monday. The suspect, Francisco Sanchez - a Mexican national who has been deported five times and is accused of shooting Kathryn Steinle, 32 - was in the custody of the San Francisco Sheriff's Department on March 26, but was let go, it has been revealed. Sanchez, 45, was brought in on a decade-old drug charge, but was released on April 15 when the charges were dropped - just over two months before the murder on July 1.Kathryn Steinle, 32, was shot dead as she strolled along Pier 14 in San Francisco with her father on Pier 14Francisco Sanchez, 45, said he picked up a gun wrapped in a T-shirtClaims gun went off three times and he didn't realize he had shot SteinleImmigration and Customs Enforcement say Sanchez was taken into custody March 26 but released on April 15 without them knowing'ICE could have taken custody of him and had him removed from the country - thus preventing this terrible tragedy' officials saidSanchez, a seven-time felon, had been deported to Mexico five times 
 Question:The area is one of the busiest tourist destinations in _.

San Francisco