Computer programming help?

The static method arrayToString takes an array of Strings and returns a String that reports the contents of the array in a form illustrated by the following examples. If the arrays x, y, and z are given by:

String[] x = { "a", "b", "c", "d" };

String[] y = { "membership" };

String[] z = { };

then arrayToString( x ), arrayToString( y ), and arrayToString( z ) have the values:

"[ a, b, c, d ]"

"[ membership ]"

"[ ]"

respectively. Which of the following are suitable definitions of arrayToString?

public static String arrayToString( String[] sArr )

{

String s = "[ ";

for ( int i = 0 ; i < sArr.length ; i++ )

{

s += sArr[ i ];

if ( i + 1 < sArr.length )

s += ", ";

}

s += " ]";

return s;

}

public static String arrayToString( String[] sArr )

{

String s = "[ ";

int i = 0;

while ( i < sArr.length )

{

s += sArr[ i ] + ", ";

i++;

}

s += "]";

return s;

}

public static String arrayToString( String[] sArr )

{

String s = "[ ";

int i = 0;

while ( i + 1 < sArr.length )

{

s += sArr[ i ] + ", ";

i++;

}

if ( sArr.length > 0 )

s += sArr[ i ];

s += " ]";

return s;

}

I only

II only

I and II only

I and III only

I, II, and III