Which two of the following will return an instance of a block object? (Choose two)

A.
Mage::getBlock(‘page/html_header’);

B.
Mage::app()->createBlock(‘page/html_header’);

C.
Mage::createBlock(‘page/html_header’);

D.
Mage::app()->getLayout()->createBlock(‘page/html_header’);

E.
Mage::getLayout()->createBlock(‘page/html_header’);

F.
Mage::app()->getLayout()->createBlock(‘page/html_header’)->setTemplate(‘page/html/header=phtml’);