An HTML input element for a value that corresponds to a field on a Salesforce object. The
<apex:inputField> component respects the attributes of the associated field, including whether the
field is required or unique, and the user interface widget to display to get input from the user. For
example, if the specified <apex:inputField> component is a date field, a calendar input widget is
displayed. When used in an <apex:pageBlockSection>, <apex:inputField> tags always display
with their corresponding output label.
Note that if custom help is defined for the field in Setup, the field must be a child of an
<apex:pageBlock> or <apex:pageBlockSectionItem>, and the Salesforce page header must be
displayed for the custom help to appear on your Visualforce page. To override the display of
custom help, use the <apex:inputField> in the body of an <apex:pageBlockSectionItem>.
Consider the following when using JavaScript events with this tag:
For lookup fields, mouse events fire on both the text box and graphic icon
For multi-select picklists, all events fire, but the DOM ID is suffixed with _unselected for the left
box, _selected for the right box, and _right_arrow and _left_arrow for the graphic icons
For rich text areas, no events fire.

A.
apex:pageBlockButtons

B.
apex:define

C.
apex:outputLabel

D.
apex:inputField