Which correctly shows where a comma is needed in the sentence A. Shipping companies transport food from producers to consumers in refrigerated trucks since fresh food spoils quickly. B. Shipping compa?

The correct placement of the comma is in option B: "Shipping companies transport food from producers to consumers in refrigerated trucks, since fresh food spoils quickly." The comma is needed before "since" to separate the dependent clause "since fresh food spoils quickly" from the main clause.