Muscle tissue has all of the following properties EXCEPT:

Choice A reason: Circumduction is a circular movement that combines flexion, extension, abduction, and adduction. It is typically seen in ball-and-socket joints like the shoulder or hip, not in the neck. It does not describe the backward bending of the head.

Choice B reason: Rotation refers to the movement of a bone around its longitudinal axis, such as turning the head side to side. It does not involve bending the head backward.

Choice C reason: Hyperextension occurs when a joint is extended beyond its normal anatomical position. In the case of the head, bending it backward past the neutral anatomical position is a classic example of hyperextension.

Choice D reason: Flexion is the movement that decreases the angle between two body parts, such as bending the head forward toward the chest. It is the opposite of the movement described in the question.

acromion is a projection of another bone.

Choice B reason: The scapula is the correct answer. The acromion is a bony process on the scapula that extends laterally over the shoulder joint and articulates with the clavicle to form the acromioclavicular joint.

Choice C reason: The ulna is a forearm bone and does not have an acromion. It forms part of the elbow joint.

Choice D reason: The scaphoid is a carpal bone in the wrist and is unrelated to the shoulder girdle or the acromion.

Choice E reason: The pollex refers to the thumb and is not associated with the acromion or shoulder anatomy.