Read the passage and select the most appropriate option for the specified blank. No distractions are too minor when it comes to the Suneung, which many see as a culmination of years of formal education and which is widely regarded as a pivotal event because it determines students' (A)__________, careers, and social statuses. “I’m worried that the song will play in my head even during the exam,” one student expressed concern about (B)__________ being a distraction during the exam. Suneung students have previously been encouraged to avoid so-called earworms, with songs such as “Go Go” by BTS and “Ring Ding Dong” by SHINee repeatedly cited online as tracks that should be forbidden. Ensuring that the exam runs smoothly is a nationwide effort. The shops and stock market opened late to reduce (E)__________, and authorities adjusted public transport operating hours and put more than a dozen spare trains on standby in case of breakdowns. Authorities grounded planes during the English listening test to (C)__________. To ensure the exam runs smoothly, more than 10,000 police officers were deployed, including some tasked with (D)__________. Authorities also asked bus and taxi drivers to refrain from honking while the tests were taking place. Select the most appropriate option for blank (D): More than 10,000 police officers were deployed, including some tasked with (D)__________.

1. distributing exam materials
2. reducing noise levels near schools
3. supervising students during the test
4. ferrying students to school in emergencies