20. To include a system-provided header file, such as iostream, in a user program, you enclose the header between A. curly brackets B. angular brackets C. asterisks D. square brackets 21The value of a pointer variable is an A. address B. entry in a table C. array D. unknown value 22. An array created during the execution of a program is called a array A. static B. final C. just in time D. dynamic 23. Inheritance s an example of a(n) , relationship A. is-a B. has-a C. friend of D. member of