Definition: In this task, you're given a question, along with a context passage. The passage will not have a direct answer to the question, but can include some information and a clue for the answer. Assuming you can only obtain information about one entity in the passage, your job is to determine whether information from the passage can be used to answer the question. Indicate your choice as `a` for Yes or `b` for No.
Input: Question: How many championships had Lawson's archrival and later teammate win? Passage:Lawson accepted an offer from Yamaha to contest the 500cc World Championship as Kenny Roberts' teammate for the 1983 season. Lawson spent the 1983 season learning the ropes of the Grand Prix circuit. In 1984, Lawson began winning regularly and won the 1984 World Championship. It would mark the first of four world titles Lawson would go on to win. In 1985, he won the prestigious Imola 200 pre-season race. After winning two more titles for Yamaha in 1986 and 1988, Lawson shocked the racing world by announcing he would be leaving Yamaha to sign with their arch-rivals Rothmans Honda as teammate to his own archrival, Australia's 1987 World Champion Wayne Gardner. By switching teams, Lawson also fulfilled his desire to work with Erv Kanemoto. After Gardner crashed and broke his leg during the third round at Laguna Seca, Lawson went on to win the 1989 title for Honda, becoming the first rider to win back-to-back championships on machines from different manufacturers. By winning with both Yamaha and Honda, Lawson silenced his critics who believed he would not be as successful away from the factory Marlboro Yamaha team.


b