The limits of percentage p of the longitudinal reinforce-ment in a column is given by A. 0.15% to 2% B. 0.8% to 4% C. 0.8% to 6% D. 0.8% to 8%

The correct answer is: B. 0.8% to 4%.

The percentage of longitudinal reinforcement in a column is the ratio of the area of the longitudinal reinforcement to the gross area of the column. The minimum percentage of longitudinal reinforcement is 0.8%, and the maximum percentage of longitudinal reinforcement is 4%. The minimum percentage of longitudinal reinforcement is required to provide adequate strength and ductility, while the maximum percentage of longitudinal reinforcement is limited to prevent buckling of the column.

Option A is incorrect because the minimum percentage of longitudinal reinforcement is 0.8%, not 0.15%.

Option C is incorrect because the maximum percentage of longitudinal reinforcement is 4%, not 6%.

Option D is incorrect because the maximum percentage of longitudinal reinforcement is 4%, not 8%.