The code fragment will fail to compile because the parseInt method of the Integer class is a static method, which means that it can be invoked without creating an object of the class. However, the code is trying to invoke the parseInt method on an object of type Integer, which is not allowed. The correct way to invoke the parseInt method is by using the class name, such as Integer.parseInt (s). Therefore, the code fragment will produce a compilation error.Reference:Integer (Java SE 17 & JDK 17) - Oracle

The code snippet is an example of Java SE 17 code. The code is checking if the object is an instance of class C and if it is, it will print ''mC''. If it is not an instance of class C, it will print ''mA''. In this case, the object is not an instance of class C, so the output will be ''mA''.Reference:Pattern Matching for instanceof - Oracle Help Center

The code fragment in Option C invokes all callable objects in the workers set by using the ExecutorService's invokeAll() method. This method takes a collection of Callable objects and returns a list of Future objects representing the results of the tasks. The other options are incorrect because they either use the wrong method (invokeAny() or submit()) or have syntax errors (missing parentheses or semicolons).Reference:AbstractExecutorService (Java SE 17 & JDK 17) - Oracle

The two code fragments that compile are B and E. These are the only ones that use the correct syntax for declaring and initializing a var variable. The var keyword is a reserved type name that allows the compiler to infer the type of the variable based on the initializer expression. However, the var variable must have an initializer, and the initializer must not be null or a lambda expression. Therefore, option A is invalid because it does not have an initializer, option C is invalid because it has a null initializer, and option D is invalid because it has a lambda expression as an initializer. Option B is valid because it has a String initializer, and option E is valid because it has an int initializer.

https://docs.oracle.com/en/java/javase/17/language/local-variable-type-inference.html

The correct answer is A and F because the wordDoc class must be a non-sealed class or a final class to extend the sealed Doc class. Option B is incorrect because the wordDoc class must be non-sealed or final. Option C is incorrect because the wordDoc class cannot be in a different package than the Doc class. Option D is incorrect because the wordDoc class cannot be a sealed class. Option E is incorrect because the wordDoc class cannot be an abstract class.Reference:Oracle Certified Professional: Java SE 17 Developer,3 Sealed Classes - Oracle Help Center