Suppose A is an interface, B is a concrete class with a no-arg constructor that implements A. Which of the following is correct?
a. A a = new A();
b. A a = new B();
c. B b = new A();
d. B b = new B();
b. A a = new B();
d. B b = new B();
Since B is a concrete class with a no-arg constructor, d is correct. Since an instance of B is also an instance of A, b is also correct.
Computer Science & Information Technology
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