Person.java: public class Person { String name; int age; public Person(String n, int a) { name = n; age = a; } public String getName() { return name; } public int getAge() { return age; } }…

Question

Options

• AcheckAge (iList, () -> p. get Age () > 40);
• BcheckAge (iList, Person p -> p.getAge() > 40);
• CcheckAge (iList, p-> p.getAge() > 40);
• DcheckAge (iList, (Person p) -> {p.getAge() > 40;});

• A
  9% (3)
• B
  3% (1)
• C
  73% (24)
• D
  15% (5)

Explanation

Option C uses the correct lambda syntax for a Predicate<Person>: a single inferred-type parameter without parentheses, followed by an expression body that directly returns a boolean - which is exactly what Predicate<Person>.test(Person p) requires. Since Hank is 45, 45 > 40 evaluates to true, so he gets printed.

Why the others fail:

• A uses () (no parameters), but Predicate<Person> requires exactly one Person argument - this won't compile.
• B is a syntax error: when you explicitly declare the parameter type, parentheses are mandatory - it must be (Person p), not Person p.
• D uses a block body {...} but omits return. Inside a block body, you must write return p.getAge() > 40; - without it, the lambda returns void, which doesn't satisfy Predicate<Person>.

Memory tip: Think of the lambda rules as "brackets need brackets" - explicit type needs (), block body needs return. When in doubt, the simplest form p -> expression is always valid for a single-parameter predicate.

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