In Java, for a declaration like X implements Y, Z, which of the following statements about X, Y, and Z is correct?

Introduction / Context:
This question focuses on the correct use of the implements keyword in Java. It checks whether you know which kinds of types may appear on each side of an implements clause and how multiple interface implementation works. This is a basic but essential piece of Java syntax knowledge.

Given Data / Assumptions:

• We have the declaration X implements Y, Z.
• Statement 1 says that X should be a class.
• Statement 2 says that Y and Z should be interfaces.
• We assume standard Java syntax rules for classes and interfaces.

Concept / Approach:
In Java, the implements keyword is used only by classes or enums to indicate that they implement one or more interfaces. The type to the left of implements must therefore be a class or an enum, not an interface. The types listed to the right of implements must be interfaces. A class can implement multiple interfaces at once by separating them with commas, which is how Java supports multiple inheritance of type. An interface that wants to reuse another interface uses extends, not implements.

Step-by-Step Solution:
Step 1: Check statement 1, which says X should be a class. This is correct, because a normal declaration like class X implements Y, Z is valid Java syntax.Step 2: Check statement 2, which says Y and Z should be interfaces. This is also correct, because only interfaces can appear in the implements list.Step 3: If Y or Z were classes instead of interfaces, the declaration X implements Y, Z would be invalid.Step 4: If X were an interface, it would need to use extends, not implements, to relate to other interfaces.Step 5: Since both statements 1 and 2 are correct, option C is the right answer.

Verification / Alternative check:
To verify, try compiling class X implements Y, Z where Y and Z are interfaces and X is a class. The code compiles successfully. If you change Y into a class, the compiler reports that a class cannot implement another class. Likewise, if you change X into an interface declaration, the compiler requires extends instead of implements. These experiments confirm the correctness of statements 1 and 2.

Why Other Options Are Wrong:
Option A and option B each claim that only one of the statements is true, which contradicts Java syntax rules. Option D states that none are true, which is clearly incorrect because both the role of X and the types of Y and Z are correctly described in the original statements.

Common Pitfalls:
A common mistake is writing an interface that implements another interface instead of extending it, or trying to implement classes with implements. Another pitfall is forgetting that a class can implement several interfaces but extend only one class. Keeping these rules in mind helps you design clear and valid type hierarchies in Java.

Final Answer:
Both statements are correct: X must be a class (or enum) and Y and Z must be interfaces when you write X implements Y, Z.