The correct answer is "subclavian artery." This is the correct answer because what this question is essentially asking is which of the listed blood vessels is closest to the clavicle, and most likely to be injured by a clavicular fracture based upon its proximity to the clavicle. Of the listed vessels, the subclavian artery is located closest to the clavicle (just inferior to the clavicle bone, as the name, sub-clavian implies). As such, if the clavicle breaks and a sharp fragment is formed, it would be most likely to injure the subclavian artery. 

The internal and external carotid arteries, and jugular vein are located within the neck, but more deep and superior to the clavicle than the subclavian artery. The facial artery is located within the face and as such is located very superiorly to the clavicle bone and is unlikely to be involved by a clavicle fracture.

The frontalis muscle lifts the eyebrows and wrinkles the forehead. The brow is furrowed by the corrugator supercilii muscle, and the eye lids are raised by the levator palpebrae superioris and lowered by the orbicularis oculi.

The masseter is a quadrilateral muscle that originates from the zygomatic arch and maxilla and inserts into the coronoid process of the mandible. It's function is to lift the mandible, closing the jaw. 

The risorius is a small facial muscle that originates on the parotic fascia and inserts into the modiolus. It's primary action is to retract the corners of the mouth in smiling. The lips are pursed by the orbicularis oris. The mouth is compressed and food is kept between the teeth by the buccinator muscle. The lower lip is depressed by the depressor labii inferioris.

The orbicularis oris, a circular muscle that compresses the lips, originates on the maxilla and mandible and inserts into the skin of the lips

The depressor anguli oris is a small triangular muscle that originates on the mandible and inserts into the modiolus. It's main action is to lower the corners of the mouth in frowning. The auricular muscles are a part of the inner ear. The temporoparietalis muscle is a thin muscle covering the temporal bone, and the depressor supercilii is a muscle of the eye.

The stapedius, the smallest muscle in the human body, controls the amplitude of sound vibrations pulling on the neck of the stapes.The auriculares move the ears. The ciliary muscle and the lateral rectus are both muscles of the eye.

The superior oblique originates on the annulus of Zinn and inserts into the outer posterior eye. It's action is to depress and internally rotate the eye. 

The platysma, a sheet-like muscle that traverses the neck from the clavicle to the mouth and jaw, is innervated by the cervical branch of the facial nerve (CN VII).

The splenius capitis, one of the main extenders of the neck, has it's origin on the mastoid process of the temporal bone. The rectus capitis posterior minor, the rectus capitis posterior major, and the semispinalis capitis all originate on the nuchal line of the occipital bone.