In 2018, Kurt Luther and Vikram Mohanty created the web-based tool Civil War Photo Sleuth (CWPS). A user uploading an unknown Civil War soldier's photograph to CWPS first tags the photo with all known information. _________ CWPS's facial-recognition software analyzes twenty-seven different physical features and looks for matches to tagged images already in the database.

Which choice completes the text with the most logical transition?