Consider having three String variables a, b, and c. The statement c = a + b; also can be achieved by saying_____________.a. c = a.length( ) + b.length( );b. c = (int) a + (int) b;c. c = a.concat(b);d. c = b.concat(a);e. c = a.plus(b);

In Java Programming language the concat function in the string is used to merge the two string .it is similar with the "+" operator in string means if we use "+" between the two string this will also merge the two string .

Following are the syntax of concat function

string1.concat(string2);

For example

public class Main // main class

{

public static void main(String[] args) // main method

{

String a="san";// varible declaration

String b="ran";// varible declaration

String c;// varible declaration

c=a+b;// merge the two string

System.out.println(c);// display the string c

c=a.concat(b);//merge the two string

System.out.println(c);// display the string c

}

Output:

sanran

All the others options are not used to merge the string that's why the others option are incorrect.