Final answer:
The NSC would likely contact a carrier through Email or Phone call, as these are the most common and professional communication methods used today. Fax is also a possibility, though less common.
Step-by-step explanation:
When the NSC (National Safety Council) needs to contact a carrier for purposes related to transportation safety, compliance, or other official business, they would most likely use modern and professional communication methods. The options provided, such as Email (A), Phone call (B), and Fax (D), are all viable means through which organizations typically communicate. Carrier pigeon (C) is an antiquated and non-professional method that would not be used in this context. Email and phone calls are the most common methods of communication in the business world today, as they are fast, reliable, and provide a record of correspondence. Though less common now, fax might still be used in certain scenarios where a physical document needs to be sent quickly, and a digital scan is not available or appropriate.
Therefore, the most likely methods the NSC would use to contact a carrier would be either Email or Phone call, with Fax being a less common, but still possible, method.