Question: The Subaru Legacy is considered an alternative to which BMW entry-level luxury car?

Context paragraphs:
BMW 3 Series: The BMW 3 Series is an entry-level luxury car manufactured by the German automaker BMW since May 1975.  It is the successor to the 02 Series and has been produced in six different generations.

BMW 3 Series (E30): The BMW E30 is an entry-level luxury car which was produced by BMW from 1982 to 1994.  The initial models used the coupe (two-door sedan) body style.  Four-door sedan models were introduced in 1983, convertibles were introduced in 1985 and estate ("Touring") models were introduced in 1987.  The E36 replaced the E30 coupe models in 1990, with other E30 body styles being phased out of production until the final E30 model, a Touring, was produced in 1994.

Compact executive car: A compact executive car is a premium car smaller than an executive car.  In European classification, compact executive cars are part of the D-segment.  In North American terms, close equivalents are "compact premium car", "compact luxury car", "entry-level luxury car" and "near-luxury car".  Compact executive cars are usually available in saloon, estate, coupé, and cabriolet body styles.

Lancia Beta: The Lancia Beta (Type 828) was an entry-level luxury car produced by Italian car manufacturer Lancia from 1972 to 1984.  It was the first new model introduced by Lancia after it had been taken over by Fiat in 1969.

Cadillac BLS: The Cadillac BLS is an entry-level luxury car marketed in Europe by Cadillac.  Based on General Motors' Epsilon architecture, the BLS was a heavily restyled version of the Saab 9-3.  The development was done by Saab and the car cost more than one billion kronor (approximately $140 million) to design.  It was manufactured in Trollhättan, Sweden, alongside the Saab 9-3 and the Saab 9-5.  Sales of the sedan began in March 2006, with a station wagon joining the line for 2007.  The BLS was introduced to the Arabian, Mexican, South African, and South Korean markets for the 2007 model year.

Subaru Legacy (first generation): The first generation Subaru Legacy is a mid-size family car / wagon developed by Fuji Heavy Industries.  The Legacy was an all new model, and was considered a notable departure from Subaru products in the past.

Subaru Legacy: The Subaru Legacy is a mid-size car built by Japanese automobile manufacturer Subaru since 1989.  Part of the original design goals for the Legacy model was to provide Subaru a vehicle in which they could compete in the lucrative North American midsize market against competitors Honda Accord, Toyota Camry, Mazda6, and Nissan Altima.  Higher performance variants of the Legacy are offered as competitive alternatives to compact executive cars such as the Audi A4, Alfa Romeo 159 and BMW 3 Series.  The Legacy also serves as Subaru's flagship car.

Acura TSX: The Acura TSX is a medium-sized entry-level luxury car that was manufactured by Acura.  Introduced in April 2003 as a 2004 model, it was sold only in the United States and Canada, but since the 2009 model year it has also been available in Mexico.  It is also sold in Guam and Puerto Rico.  It is sold in North America under the Acura luxury marque, where it filled the gap as Acura's 4-door, entry-level sedan when the Integra sedan was discontinued in 2001 (1996 in Canada since the EL was the Integra sedan's replacement there).  The TSX would also eventually replace the Acura RSX in the US (which in turn succeeded the Acura Integra coupe).  From 2008 until 2013, the TSX was the smallest vehicle in the Acura model line, other than the Civic-based CSX (and the preceding 1.6/1.7EL) sold only in Canada.  In 2013, the smaller ILX was introduced in both the United States and Canada, based upon the Civic platform (replacing the CSX in Canada).  All TSXs were built in Sayama, Saitama, Japan.

Subaru Outback: The Subaru Outback is an automotive nameplate used by the Japanese automobile manufacturer Fuji Heavy Industries (FHI) since 1994.  The "Outback" name has been utilized on two different Subaru branded vehicles.  One of these models is based on the mid-sized Subaru Legacy and the other derived from the hatchback version of the Subaru Impreza.  The model is named after the vast, remote, and arid outback regions in Australia; the name is intended to emphasize the moderate off-road capability of the vehicle, while also giving a nod to the original design, which had a larger trunk "out back" than the Legacy.

Subaru Tribeca: The Subaru Tribeca is a mid-size crossover SUV sold since 2005 by Subaru.  Released in some markets, including Canada, as the Subaru B9 Tribeca, the name "Tribeca" derives from the Tribeca neighborhood of New York City.  Built on the Subaru Legacy platform and sold in five- and seven-seat configurations, the Tribeca was intended to be sold alongside a slightly revised version known as the Saab 9-6.  Saab, at the time a subsidiary of General Motors (GM), abandoned the 9-6 program just prior to its release subsequent to GM's 2005 divestiture of its 20 percent stake in FHI.

Supporting paragraphs: Subaru Legacy BMW 3 Series
Answer: BMW 3 Series