Many events require temporary structures, such as grandstands, stages, scaffold, tent and roof structures. The failure of any temporary structure, no matter how small, in a crowded, confined space could have devastating effects. It is therefore essential to design and erect structures to suit the specific intended purpose and to recognize that the key to safety of these structures is largely in the: A. Choice of appropriate design and materials B Correct positioning C. Proper planning and control of work practices D. Careful inspection of the finished product E. A & B only F. All of the above