Question: Which canal's cargo was primarily coal, the Cape Cod Canal or the Chesapeake and Ohio Canal?

Context paragraphs:
Cape Cod Canal Railroad Bridge: The Cape Cod Canal Railroad Bridge (also known as the Buzzards Bay Railroad Bridge), a vertical lift bridge in Bourne, Massachusetts near Buzzards Bay, carries railroad traffic across the Cape Cod Canal, connecting Cape Cod with the mainland.

Coast Guard Station Cape Cod Canal: United States Coast Guard Station Cape Cod Canal is a United States Coast Guard station located in Sandwich, Massachusetts.  It operates patrol boats along the coast of Cape Cod, the Cape Cod Canal, and the treacherous waters of Buzzards Bay.

Sagamore Beach, Massachusetts: Sagamore Beach is a village of Bourne, Massachusetts fronting Cape Cod Bay and the east end of the Cape Cod Canal.  It occupies the northern half of the Sagamore census-designated place.  Along with Buzzards Bay and Bournedale, it is one of only three communities in Barnstable County that are north of the Cape Cod Canal.

Third Cape Cod Canal road bridge: The Third Cape Cod Canal road bridge is a proposed bridge that would cross the Cape Cod Canal in Bourne, Massachusetts.  Due to gridlock during peak summer months, and growing traffic issues even off-season, the need for a third canal crossing has been a topic of discussion for many years.  The concept of a third crossing has gained steam in recent years, culminating in a proposal for a toll bridge that would either sit directly between the existing bridges or adjacent to one of them.

Cape Cod Canal: The Cape Cod Canal is an artificial waterway in the U.S. state of Massachusetts connecting Cape Cod Bay in the north to Buzzards Bay in the south.

Scusset Beach State Reservation: Scusset Beach State Reservation is a state-operated, public recreation area located in the town of Sandwich in Barnstable County, Massachusetts, at the east end of the Cape Cod Canal on land formerly part of Sagamore Hill Military Reservation.  In addition to its beach and campgrounds, prominent features of the park include Sagamore Hill, a one-time Native American meeting ground and site of World War II coastal fortifications, and a 3000 ft stone jetty that separates the canal and beach.  Unlike most of Sandwich, this section of the town is on the mainland side of the Cape Cod Canal.  The state park is managed by the Massachusetts Department of Conservation and Recreation under a lease agreement with the U.S. Army Corps of Engineers.

Bournedale, Massachusetts: Bournedale is a village in the town of Bourne in Barnstable County, Massachusetts fronting Sagamore Beach, Buzzards Bay and the middle of the Cape Cod Canal.  Along with Buzzards Bay and Sagamore Beach it is one of only three communities in Barnstable County that are north of the Cape Cod Canal.  Another region in Barnstable County that are north of the Cape Cod Canal is Scusset Beach State Reservation.

Chesapeake and Ohio Canal: The Chesapeake and Ohio Canal, abbreviated as the C&O Canal and occasionally called the "Grand Old Ditch," operated from 1831 until 1924 along the Potomac River from Washington, D.C., to Cumberland, Maryland.  The canal's principal cargo was coal from the Allegheny Mountains.

Cape Cod Canal Tunnel: The Cape Cod Canal Tunnel is a fictional tunnel allegedly built in the 1960s under the Cape Cod Canal.  The hoax has been popularized by the selling of bumper sticker permits.  It came into popular usage in Massachusetts as a commentary on often severe traffic on the bridges that lead to Cape Cod.  It has also been used by locals trying to trick tourists, directing them to a nonexistent entrance near the Massachusetts Military Reservation.  The other entrance of the tunnel supposedly exists in New Bedford.

Jeremiah's Gutter: Jeremiah's Gutter was a canal located on the border of Orleans and Eastham, Massachusetts, the first canal to cut across the peninsula of Cape Cod.  It connected Cape Cod Bay in the west to the Atlantic Ocean in the east.  It was active for over 100 years, although it gradually fell out of use and was later replaced by the more widely known Cape Cod Canal.

Supporting paragraphs: Cape Cod Canal Chesapeake and Ohio Canal
Answer: Chesapeake and Ohio Canal