ios programming error: ARC forbids explicit message send of''retain'

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C

Objective-C

iOS

Xcode

Hi I impored ARC but I got same error, I am using xcode 4.6 .
Thanks for your help

@implementation any
-(void)viewDidLoad{
contentArray=[[NSArray arrayWithObjects:@"a",@"b",@"c",Nill]retain];//error ARC forbids explicit message send of''retain'
[super viewDidLoad];
}