Practice · 2 of 4
Master MCQ
CHALLENGE
Difficulty: advanced+25 XP
What does mystery("racecar") return?
``java
public static boolean mystery(String s) {
return rev(s).equals(s);
}
public static String rev(String s) {
if (s.length() <= 1) { return s; }
return rev(s.substring(1)) + s.charAt(0);
}
``
A. true
B. false
C. the empty string
D. StackOverflowError
Print the letter, then your one-sentence justification.
Press Submit to check your solution.
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