Answer:
b. TRUE
Explanation:
Whenever they are passed as parameters to a function, the IO classes istream and ostream must be passed using a pass-by-reference parameter passing scheme.
This is because , assuming a pass by value semantics would require us to copy the value of the istream or ostream object which would be meaningless. In fact these objects don't even have a copy constructor at all. So such objects are always passed by reference.