Contact pressure beneath a rigid footing resting on cohesive soil is A. less at edges compared to middle B. more at edges compared to middle C. uniform throughout D. none of the above

The correct answer is: A. less at edges compared to middle.

The contact pressure beneath a rigid footing resting on cohesive soil is less at edges compared to middle. This is because the soil at the edges of the footing is subjected to a greater tensile stress than the soil at the middle of the footing. The tensile stress causes the soil at the edges to deform more than the soil at the middle, which results in a lower contact pressure.

Option B is incorrect because the contact pressure is actually less at the edges than at the middle. Option C is incorrect because the contact pressure is not uniform throughout. Option D is incorrect because the contact pressure is not zero at the edges.