Question: Dudley square and the Silver line are both part of what?

Context paragraphs:
Pershing Square station: Pershing Square is a heavy-rail subway station in the Los Angeles County Metro Rail system.  It is located on Hill Street between 4th and 5th Streets, near Pershing Square in Downtown Los Angeles.  This station is served by the Metro Red Line and the Metro Purple Line and various local bus services.  The Metro Silver Line heading northbound to El Monte Station stops at the street level (Olive / 5th Street).  The Metro Silver Line heading southbound to Harbor Gateway Transit Center does not stop near the station.  The station uses an island platform layout and is decorated with a neon art piece by Stephen Antonakos.  The work pays tribute to the first neon sign in the United States, which was hung in 1924 in the Pershing Square area.  The station installed station canopies for the stations entrance in 2014.  Pershing Square is near Angels Flight and Grand Central parking.

Silver Line (MBTA): The Silver Line is the bus rapid transit (BRT) system of the Massachusetts Bay Transportation Authority (MBTA).  It currently operates four routes in two sections that were built in separate phases.

Harbor Transitway: The Harbor Transitway is an 11 mi shared-use bus corridor (transitway) and high-occupany toll roadway that runs in the median of Interstate 110 (Harbor Freeway) in Southern California.  The main bus service operating on the busway is the Metro Silver Line which was introduced on December 13, 2009.  The Metro Silver Line bus rapid transit line runs on the Harbor Transitway from Harbor Gateway Transit Center to Downtown Los Angeles and continues to El Monte Bus Station.  The line operates daily with frequent service.  In addition to Metro Silver Line, other Metro bus and municipal bus routes also operate on the Harbor Transitway.  They include Metro Express lines 442, 460 and 550, Torrance Transit line 4, Gardena Transit line 1X and Orange County Transportation Authority lines 701, 721.  Metro Express lines 442 and 550 operate only during weekdays peak hours.  Metro Line 442 operates peak a.m. northbound only and southbound p.m. only.  Torrance Transit line 4, Gardena Transit line 1X, and Orange County Transportation Authority: 701, 721 operate only during weekday peak hours.  Metro Express line 460 operates daily along with the Metro Silver Line.  Busway bus lines originate from Downtown Los Angeles and El Monte, with final destinations in Disneyland, and Disney California Adventure Park located in Anaheim, Knott's Berry Farm, Artesia, Fullerton, Gardena, Hawthorne, Huntington Beach, San Pedro and Torrance.

Harbor Gateway Transit Center: Harbor Gateway Transit Center (formerly Artesia Transit Center) is a Metro Silver Line station and a large bus station at southern end of the Harbor Transitway located in the southwest corner of Interstate 110 (Harbor Freeway) and State Route 91 (Gardena Freeway) in Harbor Gateway close to Carson.  The station has 12 bus bays and 900 park and ride spaces, and is the southern terminus of the Metro Silver Line (line 910 only).  Many passengers connect to this station from other buses to transfer to the Silver Line.  Public restrooms for passengers as began installation in October 2012 and opened in February 2013.  The nextrip bus screens were installed in November 2012 and became fully functional in April 2013.  The large hub is undergoing station improvements.

Dudley Square (MBTA station): Dudley Square (variously known as Dudley Station, Dudley Street Terminal, or simply Dudley) is a ground-level bus station located in Dudley Square, Roxbury, Boston, Massachusetts, United States.  It is a transfer point between 17 Massachusetts Bay Transportation Authority bus routes, including two Silver Line bus rapid transit lines and 15 local MBTA Bus routes.  Like all MBTA bus stops, Dudley is fully handicapped accessible.

Melnea Cass Boulevard: Melnea Cass Boulevard is a street in Boston, Massachusetts, located between Dudley Square in Roxbury and the South End.  It is named after local community and civil rights activist Melnea Cass.  The road's right-of-way was originally planned to be part of Interstate 695, until its cancellation.  There is also an MBTA Silver Line station named Melnea Cass Boulevard on this street.

LATTC/Ortho Institute station: LATTC/Ortho Institute, officially Los Angeles Trade-Technical College/Orthopaedic Institute for Children (formerly 23rd Street), is an at-grade light rail station in the Los Angeles County Metro Rail system, located on Flower Street at 23rd Street, in the North University Park neighborhood of Los Angeles.  This station is served by the Expo Line.  It is also served by the Metro Silver Line.  Northbound Silver Line buses to Downtown Los Angeles stop at Figueroa St./23rd Street.  Southbound Silver Line buses to Harbor Gateway Transit Center/Pacific/21st Street stop at Flower St./ 23rd Street.

Harbor Beacon Park &amp; Ride: Harbor Beacon Park & Ride is a park and ride lot served by the Metro Silver Line bus rapid transit line in San Pedro, California.  The 246 space lot is located at 515 N Beacon St, San Pedro.  This stop is served by Silver Line buses in both directions.  Northbound Silver Line buses head to Downtown Los Angeles and continues eastward to El Monte via the El Monte Busway and the Harbor Transitway.  Southbound Silver Line buses continue southward in San Pedro, California to Pacific/ 21st Street.  Prior to the Metro Silver Line San Pedro Extension on December 14, 2015, bus service between Downtown Los Angeles and the Harbor Gateway Transit Center was formerly servied by Metro Express Line 450.

37th Street/USC station: 37th Street/USC is a Metro Silver Line Station on the Harbor Transitway on the Interstate 110 (Harbor Freeway) at its overcrossing of 37th Street close to the University of Southern California.  Local buses operate from Figueroa St. & Exposition Blvd.  The nearby Jefferson/USC station served by the Metro Expo Line is 1/4 mile block from the station.  The station is well utilized by USC students as it provides a close walk to the university campus.  There is no direct connection between the Metro Expo Line station and the 37th Street/USC Metro Silver Line Station.  It is the northernmost station on the Harbor transitway with buses operating on surface streets into downtown Los Angeles.  The station opened on June 1996.  The station was re-branded as a station for the Metro Silver Line when the line began service on December 13, 2009.  It is currently the only station served by the Metro Silver Line and on the Harbor Transitway to feature a sound wall to reduce noise coming from the freeway.

Alternatives for Community and Environment: Alternatives for Community and Environment (ACE) is an environmental justice community organization based in Boston's Dudley Square.  Founded in 1994, ACE works to eradicate environmental racism and classism and achieve environmental justice.  Its four core program areas are the Dudley Square Organizing Project (DSOP), Roxbury Environmental Empowerment Project (REEP), T Riders Union (TRU), and Environmental Justice Legal Services (EJLS).

Supporting paragraphs: Dudley Square (MBTA station) Silver Line (MBTA)
Answer: MBTA