Final answer:
Spica splints are designed to maintain a limb in an extended position to reduce movement for healing purposes. The term for a muscle that moves a limb away from the body is 'abductor'.
Step-by-step explanation:
Spica splints are used to keep a limb in extension in order to reduce the mobility of the affected limb. The correct answer to the question is option a. Extension. In the limbs, flexion decreases the angle between the bones, while extension increases the angle and straightens the joint. A Spica splint immobilizes the limb to allow for proper healing by maintaining the affected area in an extended position.
Addressing the second question, the term that would be used in the name of a muscle that moves the leg away from the body is d. abductor. Abduction moves the limb laterally away from the midline of the body, whereas adduction draws the limb closer. Therefore, muscles facilitating leg movement away from the body's midline are called abductors.