instruction: Extract the airlines mentioned in the text and separate them with a comma.  Which one operated the shortest flight?
context: In June 2017 after 30 months in commercial operation, 80 A350s were in service with 12 operators, the largest being Qatar Airways with 17 and 13 each at Cathay Pacific and Singapore Airlines (SIA). The fleet average block time (time between pushback and destination gate arrival) was 7.2 hours with 53% below 3,000 nmi (5,556 km), 16% over 5,000 nmi (9,260 km), and 31% in between. LATAM Airlines had the longest average sector at 10.7 hours, and Asiana had the shortest at 3.8 hours. Singapore Airlines operated the longest leg, Singapore to San Francisco 7,340 nmi (13,594 km), and the shortest leg, Singapore to Kuala Lumpur 160 nmi (296 km). Seating varied from 253 for Singapore Airlines to 389 for Air Caraïbes, with most between 280 and 320.
response: Qatar Airways, Cathay Pacific, Singapore Airlines, LATAM Airlines, Air Caraïbes.  Singapore Airlines operated the shortest flight.