Overriding and overloading, potential mix-up. Overriding methods to replace the original code with something different. Overloading methods to increase the number of methods available.
Constructors and their (default) construction. No-arg constructors, particularly default ones, are needed else beware of pitfalls in the super callers.
A brief look on static, static methods cannot access non-static variables and methods.
Misreading questions is hazardous to one's answers.