In Objective-C programming, error handling is provided with (...) class available in Foundation framework. An (...) object encapsulates richer and more extensible error information than is possible using only an error code or error string. The core attributes of an (...) object are an error domain (represented by a string), a domain-specific error code and a user info dictionary containing application specific information.

(...) is an abstractClass which represents a stream of data. They are used in Archiving and Unarchiving objects. (...) objects are usually used in a method that is being implemented so that the class conforms to the protocol.

The (...) method can be used to see if an object belongs to a class that implements a particular protocol.

In Objective-C, retain counts are the way in which memory is managed in Objective-C

A derived class can access all the private members of its base class if it's defined in the interface class

Which one is correct (legal) floating-point literal ?

Which of the following is the fastest?

A class can have two methods with the same name, but with different argument types.

Why should you use an autorelease pool ?

Which of the following statements is correct?

What сan you use to avoid msgSend function overhead?