The correct answer is: D. a zero-length string.
A zero-length string is a string that contains no characters. It is represented by two empty quotation marks, “”.
Option A is incorrect because an asterisk is a wildcard character. It can be used to match any character or group
of characters.Option B is incorrect because a space enclosed in single quotes is a single character.
Option C
is incorrect because the number 0 is an integer.Here is an example of how to initialize a String variable to a zero-length string:
String str = "";