Question

choose the underlined word that can be omitted from the sentence with no loss of meaning. the northbound traffic crawled slowly for miles, while the southbound traffic moved at the speed limit. northbound slowly

Explanation:

The word "slowly" just describes the manner of the traffic crawling. Omitting it still conveys that the north - bound traffic crawled for miles. The direction "northbound" is important for the contrast with south - bound traffic.

Answer:

B. slowly