Ans. is 'd' i.e., Recurrent laryngeal nerve PharyngealArchMuscular ContributionSkeletal ContributionsNerveArteryCorresponding Pouch Structures1st (mandibular arch)Muscles of mastication, Anterior belly of the digastric, Mylohyoid, Tensor tympani, Tensor veli palatiniMaxilla, mandible (only as a model for mandible not actual formation of mandible), Incus and Malleus, Meckel's cartilage, Ant. ligament of malleus, Sphenomandibular ligamentTrigeminal nerve (V2 and V3)Maxillary artery, external carotid arteryEustachian tube, middle ear, mastoid antrum, and inner layer of the tympanic membrane.2nd (hyoid archMuscles of facial expression, Buccinator, Platysma, Stapedius, Stylohoid, Posterior belly of the digastricStapes, Styloid process hyoid (lesser horn and upper part of body), Reichert's cartilage, Stylohyoid ligamentFacial nerve (VII)Stapedial Arterymiddle ear, palatine tonsils3rdStylopharyngeusHyoid (greater horn and lower part of body), thymusGlossophar- yngeal nerve (IX)Common carotid/ internal carotidInferior parathyroid, Thymus4thCricothyroid muscle, all intrinsic muscles of soft palate including levator veli palatiniThyroid cartilage, epiglottic cartilage Cuneiform cartilage Cricoid cartilage Corniculate cartilageVagus nerve (X) Superior laryngeal nerveRight 4th aortic arch subclavian artery Left 4th aortic arch: aortic archSuperior parathyroid, ultimobranchial body (which forms the Para follicular C-Cells of thyroid gland).6thAll intrinsic muscles of larynx except the cricothyroid muscleArytenoid cartilagesVagus nerve (X) Recurrent laryngeal nerveRight aortic arch: pulmonary artery Left 6th aortic arch: Pulmonary artery and ductus arteriosusRudimentary structure, becomes part of the fourth pouch contributing to thyroid C-cells.