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    Question

    The following C++ code has a compilation error. How can

    you correct it to properly use the abstract base class `Printer`? #include class Printer { public:     virtual void print() = 0; }; class LaserPrinter : public Printer { public:     void print() {         std::cout
    A The code is already correct; there is no error. Correct Answer Incorrect Answer
    B Change `virtual void print() = 0;` to `void print() {};`. Correct Answer Incorrect Answer
    C Remove the `override` keyword from `LaserPrinter::print()`. Correct Answer Incorrect Answer
    D Make `LaserPrinter` an abstract class. Correct Answer Incorrect Answer
    E Change `Printer* p = new LaserPrinter();` to `LaserPrinter* p = new LaserPrinter();`. Correct Answer Incorrect Answer

    Solution

    o The Printer class is correctly defined as an abstract base class because it has a pure virtual function print() (virtual void print() = 0;). o The LaserPrinter class correctly inherits from Printer and provides a concrete implementation for the print() method using override. This makes LaserPrinter a concrete (instantiable) class. o In main, Printer* p = new LaserPrinter(); demonstrates polymorphism. A pointer to the base class (Printer*) can point to an object of a derived class (LaserPrinter). This is perfectly valid and common practice in C++ for working with abstract classes. o The p->print(); call will correctly invoke LaserPrinter::print() due to virtual function dispatch. o delete p; correctly deallocates the dynamically allocated LaserPrinter object. o Therefore, the provided code is syntactically and logically correct and will compile and run without errors.

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