Question: The Jaguar C-XF, was a concept car that was designed to showcase the preliminary styling cues of which yet to be announced executive/mid-size luxury car, and estate produced by which British car?
Context: The Jaguar XF is an executive/mid-size luxury car and estate produced by British car manufacturer Jaguar.  It was first unveiled in autumn 2007 as a replacement for the Jaguar S-Type. The Buick Y-Job was the auto industry's first concept car, produced by Buick in 1938.  Designed by Harley J. Earl, the car had power-operated hidden headlamps, a "gunsight" hood ornament, electric windows, wraparound bumpers, flush door handles, and prefigured styling cues used by Buick until the 1950s and the vertical waterfall grille design still used by Buick today.  It used a Buick Super chassis, indicated by the word "Super" located above the rear license plate. The Jaguar C-XF (for Concept-XF) was a concept car that was designed to showcase the preliminary styling cues of the yet to be announced Jaguar XF.  The C-XF was unveiled in the 2007 North American International Auto Show with the production XF announced in the autumn of 2007 at the Frankfurt Motor Show. The Rolls-Royce Corniche is a two-door, four-seater luxury car with a cabriolet body, made in the United Kingdom from 2000 to 2002.  Rolls-Royce's flagship car, it was the fifth model to bear the Corniche name on its debut in January 2000.  At the time of its release, it was the most expensive vehicle offered by Rolls-Royce, with a base price of US$359,900.  Styling cues were taken from the Rolls-Royce Silver Seraph sedan, but it shares little mechanically with that BMW-engined car.  Instead, the Corniche's body was set onto the older platform used for the similarly-styled Bentley Azure, making it the first and only Rolls-Royce descended from a Bentley rather than the other way around. The Dodge MAXXcab is a four-door sport utility pickup truck concept car developed by Dodge.  Unveiled at the 2000 Detroit Auto Show, it was billed by Dodge as a "Passenger Priority Truck".  It shares styling cues from other vehicles in the Dodge and Chrysler line up, and is based on a modified Dodge Dakota chassis.  It features nimble, sedan-like handling, a shortened utility bed, and a minivan style interior with seating for five people, the rear bench having built in child seats.  It is powered by Dodge's 4.7L Magnum V-8, mated to a multi-speed electronic automatic transmission.  While not intended for production, the MAXXcab did showcase features that were to be found on subsequent Dodge products, such as the idea of making a pickup truck more centered on the passengers was utilized in the Dodge Ram Mega Cab, which was available starting in the 2006 model year. The Chrysler Sebring ( ) is a line of mid-size luxury automobiles that was sold from 1995 through 2010 by Chrysler.  Three generations of convertibles, two generations of sedans, and two generations of coupes were produced.  Although the coupe shared the same name and some styling cues, it was mechanically unrelated to the other Sebring models. The Chrysler Firepower was a Dodge Viper based concept car.  It also takes some of the styling cues from the Chrysler Crossfire.  The Firepower's engine was a 6.1 L Hemi V8.  According to Chrysler, this engine produced 425 hp and could propel the vehicle to a 0-60 time of 4.5 seconds.  The concept was once featured on the cover of "Car and Driver".  Designers responsible for the design were Brian Nielander (exterior), who also worked on the ME-412 concept; and Greg Howell (interior). The Oldsmobile Antares was a 1995 concept car built by Oldsmobile.  The Antares's design was heavily based on Oldsmobile's new "Aurora-look".  Many of the Antares's styling cues (most notably the overall shape and front fascia) were showcased in the 1998 Oldsmobile Intrigue production model.  The Antares was named "Best Concept Car" by AutoWeek, at the 1995 Detroit Auto Show The Jaguar F-Pace (codename X761) is a mid-size luxury crossover SUV made by the British car manufacturer Jaguar, the first model to be built by Jaguar in the crossover SUV class.  It was formally announced at the 2015 North American International Auto Show in Detroit, with sales expected to commence in 2016 following an unveiling at the International Motor Show Germany in Frankfurt in September 2015.  The design of the F-Pace is based on the 2013 Jaguar C-X17 concept car. The third generation of the Ford Thunderbird is a personal luxury car produced by Ford for the 1961 to 1963 model years.  It featured new and much sleeker styling than the second generation models.  Sales were strong, if not quite up to record-breaking 1960, at 73,051 including 10,516 convertibles.  A new, larger 390 cuin FE-series V8 was the only engine available (in 1961).  The Thunderbird was 1961's Indianapolis 500 pace car, and featured prominently in US President John F. Kennedy's inaugural parade, probably aided by the appointment of Ford executive Robert McNamara as Secretary of Defense.  It shared some styling cues with the much smaller European Ford Corsair.
Answer: Jaguar XF