Assuming that GradeBook. h is found in the current directory and the iostream header file is found in the C++ Standard Library header file directory, which of the following preprocessor directives will fail to find its desired header file?
Answer
a. #include "GradeBook. h"
b. #include
c. #include "iostream"
d. #include

#include

Explanation:

iostream is basically a header file which is included by the #include preprocessor directive and jostream contains the input output functions.

GradeBook is a class and #include preprocessor directive is used to include definition of class GradeBook

So #include will fail to find its desired header file.

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