problem with NSDictionary and JSON

Hello,

I have to separate the tokens from the contents of URL
But didnt get the required result
Following are the code lines
Any help will be appreciated!! I am new to iphone...
So please help!!!

NSURL *url = [NSURL URLWithString"http://example.com//sample.php"];
NSMutableURLRequest *urlRequest = [NSMutableURLRequest requestWithURL:url];

NSError *error=NULL;

NSData *result = [NSURLConnection sendSynchronousRequest:urlRequest returningResponse:&response error:&error];

NSDictionary *dictionary = [[CJSONDeserializer deserializer] deserializeAsDictionary:result error:&error];

NSMutableString *rowData;
int i;

for ( i=0 ; i < [[dictionary objectForKey"question"] count] ; i++)
{
[rowData appendFormat"%@ \n",[[[ dictionary objectForKey"question"] objectAtIndex:i] objectForKey"title"]];
}

[QLabel setText:rowData ];