Question: What Class II freight railroad line does the Orford Express operate on seasonally? 

Context paragraphs:
Montreal, Maine and Atlantic Railway: The Montreal, Maine and Atlantic Railway (reporting mark MMA) was a Class II freight railroad that operated in the U.S. states of Maine and Vermont and the Canadian province of Quebec between 2002 and 2014.  It was headquartered in Hermon, Maine.

Maine Central class S 2-8-2: Maine Central Railroad Class S locomotives were intended for heavy freight service.  They were of 2-8-2 wheel arrangement in the Whyte notation, or " 1'D1' " in UIC classification.  They replaced earlier class W 2-8-0 locomotives beginning in 1914.  They were the largest and most modern steam freight locomotives built for Maine Central; although former Boston and Maine Railroad 2-10-2s were later purchased to handle World War II freight traffic.  Class S locomotives pulled freight trains over the main line between Portland and Bangor, Maine; and are best remembered for service on the Mountain Division from 1929, when the class X Mallet locomotives were scrapped, until replacement by diesel locomotives in the early 1950s.

New Bedford Subdivision: The New Bedford Subdivision is a Freight railroad line in the U.S. state of Massachusetts owned by the Massachusetts Bay Transit Authority, with freight operations handled by the Massachusetts Coastal Railroad.  The line runs from the end of the CSX Middleboro Subdivision near Weir Village (in Taunton) south to New Bedford along a former New York, New Haven and Hartford Railroad line.  It junctions the Fall River Subdivision at Myricks (in Berkley).

Oak Point Yard: The Oak Point Yard is a freight railroad yard located in the South Bronx, New York City.  The yard is owned by CSX Transportation, and is a base for CSX's local deliveries in the area, including to the Hunts Point Cooperative Market and for trains that interchange freight with the New York and Atlantic Railway at Fresh Pond Junction in Queens.  CP Rail formerly handled some freight in and out of Oak Point, but during late 2010 entered a haulage-rights agreement with CSX under which CSX handles and forwards its local traffic between Oak Point and the Albany, New York area.  Stone-hauling trains belonging to the Providence & Worcester Railroad operate through Oak Point during trips between New Haven, Connecticut and the NY&A at Fresh Pond, but no P&W freight is actually handled in the yard.  Amtrak owns and operates two electrified tracks for the Northeast Corridor Line, on the northwest side of the yard.  CSX uses the Oak Point Link, a connecting track along the Harlem River, to travel between the yard and the Metro-North Hudson Line, which is its primary access route into New York, while the P&W stone trains enter via the Northeast Corridor line to the northeast.  CSX and P&W trains to Fresh Pond cross the Hell Gate Bridge onto Long Island.

Bordentown Secondary: The Bordentown Secondary was originally a freight railroad line in New Jersey, running from Pavonia Yard in Camden to Trenton.  Today, a large portion of the line from Bordentown to Camden is used for New Jersey Transit's River Line light rail service.  Conrail Shared Assets Operations continues to operate freight trains on the line, but these operations are restricted to overnight hours.

Rapid City, Black Hills and Western Railroad: The Rapid City, Black Hills and Western Railroad, also known simply as the Black Hills and Western Railroad and commonly referred to as the Rapid Canyon Line or the Crouch Line, is a defunct standard gauge freight railroad line that operated in the Black Hills in the U.S. state of South Dakota.  The railroad became known throughout the area for its crookedness and later became a tourist attraction.  It ran from Rapid City to Mystic for a distance of 36.043 miles.  The railroad ceased operations in 1947.

Orford Express: The Orford Express, a tourist train between Magog and Sherbrooke, Quebec, operates seasonally on the former Montreal, Maine and Atlantic Railway line through Quebec's Eastern Townships.  A dinner train which operated from early May to end-December, it is owned and operated separately from the underlying tracks.

Ballard Terminal Railroad: The Ballard Terminal Railroad Company LLC (reporting mark BDTL) operates three Class III short line terminal railroads in western Washington, United States.  Founded in 1997 to operate a three-mile spur through Seattle's Ballard neighborhood, the Ballard Terminal Railroad has expanded to operate two additional lines in the Puget Sound area, including Eastside Freight Railroad (reporting mark EFRX) from Snohomish to Woodinville, Washington, and Meeker Southern Railroad (reporting mark MSN) , a 5 mi segment from East Puyallup ("Meeker") to McMillin, Washington.

Old Colony Railroad: The Old Colony Railroad (OC) was a major railroad system, mainly covering southeastern Massachusetts and parts of Rhode Island.  It operated from 1845 to 1893.  Old Colony trains ran from Boston to points such as Plymouth, Fall River, New Bedford, Newport, Providence, Fitchburg, Lowell and Cape Cod.  For many years the Old Colony Railroad Company also operated steamboat and ferry lines, including those of the Fall River Line with express train service from Boston to its wharf in Fall River where passengers boarded luxury liners to New York City.  The company also briefly operated a railroad line on Martha's Vineyard, as well as the freight-only Union Freight Railroad in Boston.  The OC was named after the "Old Colony", the nickname for the Plymouth Colony.

Fall River Subdivision: The Fall River Subdivision is a Freight railroad line in the U.S. state of Massachusetts owned by the Massachusetts Bay Transit Authority, with freight operations handled by the Massachusetts Coastal Railroad; it was formerly owned and operated by CSX Transportation.  The line runs from the New Bedford Subdivision at Myricks (in Berkley) south to Fall River along a former New York, New Haven and Hartford Railroad line.  At its south end, at the Rhode Island state line in Fall River, it becomes a line of the Providence and Worcester Railroad.

Supporting paragraphs: Orford Express Montreal, Maine and Atlantic Railway
Answer: Montreal, Maine and Atlantic Railway