Which of the following statements about constructors are true? check all that apply.
a. a constructor is the code that is called when you use the 'new' keyword.
b. a constructor is declared without a return type.

a. Partly True

b. True

Explanation:

(a) "new" keyword or syntax is used for the constructors while working in Perl and Moose object system for Perl.

For Visual Basics .Net, keyword "New" is used

For Python, "___new___" is used which allocates memory for instance and receives class as an argument.

For Objective-C, "alloc" and "init" are used for constructor method. "alloc" allocates memory for the instance and "init" handles the bulk of initializing the instance. Whereas, the "new" keyword calls both "alloc" and "init" for class instance.

(b) A constructor does not return any value because it is called by the memory allocation and object initialization code  in the runtime and not directly by your code.