Which of the following methods manages the execution of work items in a queue?

Which class object is used to perform certain tasks, in response of a delivered notification?

Which class is used to find and monitor the available capture devices on a system (iphone/ipad)?

Which Messages framework classes is used to create and update messages?

Which of the following classes defines an object, which specifies if the widget has content to display?

Grand Central Dispatch (GCD) provides functions to access several common dispatch queues in an application. Which of the following functions, when called from inside a block object, returns the queue, to which the block was originally submitted for queuing?

What is the use of creating outlets for objects in iOS applications?

Which setting is optional while submitting an app to the Apple App Store?

What is the use of 'Disabled' attribute of a Text Field object?

Which is the correct declaration of an input text field with the title, 'input2'?

Which attribute in Xcode 4.x, enables you to display 'Comment' as a text inside a text field, as given in the image?