Answer: C, 6.
Answer: Boston Dynamics robots have six axes.
One axis: controls the robot to turn left and right.
Two-axis: controls the speed at which the robot moves.
Three axes: control the rotation of the robot's small arm.
Four-axis: controls the rotation of the robot's boom.
Five-axis: control the extension of the left and right arms of the robot.
Six axes: control the rotation of the robot's chest camera or tool.