有一个键值对RDD,名称为pairRDD,它包含4个元素,分别是(“Hadoop”,1)、(“Spark”,1)、(“Hive”,1)和(“Spark”,1),则pairRDD.reduceByKey((a,b)=>a+b)执行结果得到的RDD,它里面包含的元素是
A.
(“Hadoop”,1),(“Spark”,2),(“Hive”,2)
B.
(“Hadoop”,1),(“Spark”,2),(“Hive”,1)
C.
(“Hadoop”,2),(“Spark”,2),(“Hive”,2)
D.
(“Hadoop”,2),(“Spark”,1),(“Hive”,1)