21 Which Java expression can be used to check whether the web container is currently
configured to track sessions via URL rewriting?
(A) servletContext.getSessionCookiesConfiq() .isHttpOnly()
(B) servletContext.getSessionCookiesConfiq() .isSecure()
(C) servletContext.getDefaultSessionTrackingModes() .contains(SessionTrackingMode.URL)
(D) servletContext.getEffectiveSessionTrackingModes() .contains (SessionTrackingMode.URL)