Explanation: The frequency 2182 kHz is the international voice distress and calling frequency for maritime radio. To ensure that distress calls can be heard without interference, international regulations, such as those found in ITU Radio Regulations and FCC Part 80, mandate specific listening periods and silent periods. A 3-minute silent period is observed twice an hour on 2182 kHz. These periods are from the top of the hour (H+00 to H+03) and from H+30 to H+33. During these times, all non-distress transmissions must cease, and stations must maintain a watchful ear, listening exclusively for weak or distant distress calls. This standardization maximizes the chance of any station hearing a distress alert globally. Therefore, the silent periods begin at 00 and 30 minutes past the hour. The other options do not correspond to these internationally standardized distress watch periods.