Context-sensitive is most general phase-structured grammar.
A context-sensitive grammar (CSG) is a formal grammar in which the left-hand sides and right-hand sides of any production rules may be surrounded by a context of terminal and nonterminal symbols.
A context-sensitive user interface is one which can automatically choose from a multiplicity of options based on the current or previous state of the program operation. Context sensitivity is almost ubiquitous in current graphical user interfaces, usually in the form of context menus.
Option B
