Philtrum derived from:

Ans. c. Two medial nasal processIt is the shallow vertical groove seen in the midline on the outer surface of the upper lip.Philtrum of the upper lip and the premaxilla forms by the medial nasal process.The maxillary processes of the first pharyngeal arch on each side growth medially and formed upper lip. Maxillary processes meet in the midline and fuse with each other and with the medial nasal process.Thus, lateral parts of the upper lip are formed from the maxillary processes, and the medial part, or philtrum, from the medial nasal process, with contributions from the maxillary processes.The mandibular processes of the first pharyngeal arch on each side growth medially and formed the lower lip. These processes grow medially below the stomodeum and fuse in the midline to form the entire lower lip.