Answer to last one was B.
To reassure investors, a robotics startup pointed to a pilot program in which its sidewalk delivery robots logged thousands of miles without a collision. However, the pilot took place on a closed corporate campus with uniform pathways and staff members who halted foot traffic at crossings—conditions that ____ the difficulty of navigating a typical city by removing many variables, such as unpredictable pedestrians and uneven pavement.
Which choice completes the text with the most logical and precise word or phrase?