what method in order to ensure that the next filter in the filter chain is called?

A running Filter must call what method in order to ensure that the next filter in the filter chain is
called?

A.
Servlet.doFilter(Request,Response);

B.
Filter.doFilter(Request,Response);

C.
Servlet.doChain(Request,Response);

D.
FilterChain.doFilter(Request,Response);

E.
Filter.doChain(Request,Response);

F.
FilterChain.doChain(Request,Response);