A.to process the current item and return void

B.to remove an item from the end of the stream

C.to process the current item and return a stream

D.to remove an item from the beginning of the stream

A.aCount = a;

B.setCCount(c) = cCount;

C.cCount = setCCount(c);

D.tCount = tCount;

E.setGCount(g);

A.s.replace(s.indexOf("B"), s.indexOf("B"), "Q");

B.s.replace(s.indexOf("B"), s.indexOf("C"), "Q");

C.s.replace(s.indexOf("A"), s.indexOf("C"), "Q");

D.s.replace(s.indexOf("A"), s.indexOf("B"), "Q");

A.int c =list.get(0);

B.Double d = list.get(0);

C.Integer b = list.get(0);

D.Integer a = Integer.valueOf(list.get(0));

E.Double e = Double.valueOf(list.get(0));

F.double f = list.get(0);

A.10

B.0 4 9

C.nothing

D.0