Q. Which of the following statement is correct?

• (A) The sub-base course is composed of hard well burnt clinker natural gravel or any other suitable material excavated at or near the site.
• (B) The base is composed of broken stone and granular material with tar.
• (C) The wearing surface in the case of flexible pavement consists of a mixture of bituminous material and aggregate.
• (D) all of the above