Java Decision Making Quiz

Which of the following correctly describes the behavior of an `if-else` statement in Java when the condition evaluates to `false`?

• The `if` block executes and the `else` block is skipped

• Both the `if` block and the `else` block execute

• The `else` block executes and the `if` block is skipped

• Neither block executes

What will be the output of the following Java code snippet? ```java int x = 10; if (x > 5) { System.out.println("A"); } else if (x > 8) { System.out.println("B"); } else { System.out.println("C"); } ```

• A

• B

• A and B

• C

Which of the following is the correct syntax for a `switch` statement in Java?

• `switch (expression) { case value: // code break; }`

• `switch [expression] { case value => // code break; }`

• `switch (expression) { value: // code break; }`

• `switch {expression} ( case value: // code break; )`

In Java, what happens if a `break` statement is omitted in a `switch` case?

• The program throws a compile-time error

• Only the matching case executes and the switch exits automatically

• Execution falls through to the next case and continues until a `break` or end of switch

• The program skips all remaining cases and exits the switch

Which data types are valid for use as a `switch` expression in Java (Java 7 and later)?

• `int`, `float`, `String`, `char`

• `int`, `char`, `String`, `enum`

• `int`, `double`, `String`, `enum`

• `byte`, `float`, `String`, `boolean`

Consider the following Java code. What will be printed? ```java int score = 75; String grade; if (score >= 90) { grade = "A"; } else if (score >= 80) { grade = "B"; } else if (score >= 70) { grade = "C"; } else { grade = "F"; } System.out.println(grade); ```

• A

• B

• C

• F

A student writes the following Java code intending to check if a number is positive, negative, or zero. Identify the logical error and explain the corrected behavior: ```java int num = -5; if (num > 0) { System.out.println("Positive"); } if (num < 0) { System.out.println("Negative"); } if (num == 0) { System.out.println("Zero"); } ```

• There is no error; the code works correctly for all cases

• The code uses separate `if` statements instead of `else if`, meaning all three conditions are evaluated independently, but for `num = -5` it still prints "Negative" correctly

• The code will print both "Negative" and "Zero" for `num = -5` because of missing `else`

• The code will throw a runtime exception for negative numbers

A developer needs to write a Java program that assigns a discount based on membership level: "Gold" gets 30%, "Silver" gets 20%, "Bronze" gets 10%, and all others get 0%. Which implementation is most efficient and correct?

• Use nested `if` statements checking each membership level with `==` operator on Strings

• Use a `switch` statement on the membership level String with appropriate `break` statements and a `default` case returning 0%

• Use a single `if` statement with multiple conditions joined by `||` operators

• Use a `switch` statement without `break` statements to allow fall-through for all cases

Analyze the following Java code and determine what value of `result` is printed: ```java int a = 5, b = 10, c = 15; int result = 0; if (a < b) { if (b < c) { result = 1; } else { result = 2; } } else if (a == b) { result = 3; } else { result = 4; } System.out.println(result); ```

• 0

• 1

• 2

• 3

A programmer wants to evaluate a student's performance based on two conditions: attendance percentage and exam score. The student passes only if attendance is greater than or equal to 75% **and** the exam score is greater than or equal to 50, **or** if the exam score is greater than or equal to 90 regardless of attendance. Which Java decision-making statement correctly implements this logic?

• `if (attendance >= 75 && score >= 50 && score >= 90)`

• `if (attendance >= 75 || score >= 50 && score >= 90)`

• `if ((attendance >= 75 && score >= 50) || score >= 90)`

• `if (attendance >= 75 && (score >= 50 || score >= 90))`