单选题1. class SuperClass { 2. public a geta() { 3. return new a(); 4. } 5. } 6. class SubClass extends SuperClass { 7. public b geta() { 8. return new b(); 9. } 10. } Which is true?()A Compilation will succeed if a extends b.B Compilation will succeed if b extends a.C Compilation will always fail because of an error in line 7.D Compilation will always fail because of an error in line 8.
单选题
1. class SuperClass { 2. public a geta() { 3. return new a(); 4. } 5. } 6. class SubClass extends SuperClass { 7. public b geta() { 8. return new b(); 9. } 10. } Which is true?()
A
Compilation will succeed if a extends b.
B
Compilation will succeed if b extends a.
C
Compilation will always fail because of an error in line 7.
D
Compilation will always fail because of an error in line 8.
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