the diameter of the column head support a flat slab, is generally kept

The diameter of the column head support a flat slab, is generally kept

(A) 0.25 times the span length

(B) 0.25 times the diameter of the column

(C) 4.0 cm larger than the diameter of the column

(D) 5.0 cm larger than the diameter of the column

The correct Answer Is
(A) 0.25 times the span length