Given: ``java class Vehicle { String type = "4W"; int maxSpeed = 100; Vehicle(String type, int maxSpeed) { this.type = type; this.maxSpeed = maxSpeed; } } class Car extends Vehicle { String trans…

Question

class Vehicle {
 String type = "4W";
 int maxSpeed = 100;

 Vehicle(String type, int maxSpeed) {
 this.type = type;
 this.maxSpeed = maxSpeed;
 }
}

class Car extends Vehicle {
 String trans;

 Car(String trans) { //line n1
 this.trans = trans;
 }

 Car(String type, int maxSpeed, String trans) { //line n2
 super(type, maxSpeed);
 this.trans = trans;
 }
}

7. Car c1 = new Car("Auto");
8. Car c2 = new Car("4W", 150, "Manual");
9. System.out.println(c1.type + " " + c1.maxSpeed + " " + c1.trans);
10. System.out.println(c2.type + " " + c2.maxSpeed + " " + c2.trans);

Options

• A4W 100 Auto
• B4W 150 Manual
• CNull 0 Auto
• D4W 150 Manual
• ECompilation fails only at line n1
• FCompilation fails at both line n1 and line n2

• A
  5% (3)
• B
  2% (1)
• C
  2% (1)
• D
  18% (11)
• E
  64% (39)
• F
  10% (6)

Explanation

Option E is correct because Car(String trans) at line n1 does not explicitly call a super(...) constructor, so Java automatically inserts super() - but Vehicle has no no-arg constructor (defining any explicit constructor removes the default one), causing a compile error. Line n2 compiles fine because it explicitly calls super(type, maxSpeed), which matches the Vehicle(String, int) constructor exactly. Options A, B, C, and D are all wrong because they assume the code compiles and produces runtime output - it never gets that far. Option F is wrong because only n1 is broken; n2's explicit super(...) call is perfectly valid.

Memory tip: Whenever a parent class declares any constructor, assume the no-arg constructor is gone. If a subclass constructor doesn't start with an explicit super(...), Java silently tries super() - and if that doesn't exist, compilation fails immediately at that constructor.

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