The correct answer is D) swing. The extended arm with the pointed finger is the standard hand signal for instructing the crane operator to swing or rotate the crane boom in the direction the signalman is pointing. This is one of the commonly used hand signals for crane operations, as specified in OSHA regulations and industry standards. The other answer choices are incorrect because they do not match the hand signal depicted. The signals for hoisting (A), extending (B), and lowering (C) the boom involve different hand and arm positions.