The cingulum is a prominent convexity found on the lingual surface of anterior teeth, particularly in incisors and canines. It serves as a major structural feature contributing to the tooth's shape and function.

Among the options given:
- The maxillary canine has the most pronounced and well-developed cingulum. This is due to its role in guiding occlusion and providing strength during tearing of food. The cingulum on the maxillary canine is large, bulky, and often serves as a key landmark in restorative and orthodontic treatments.

- The mandibular first premolar has a relatively small or even absent cingulum, making it the least prominent among anterior teeth.

- The maxillary lateral incisor has a cingulum, but it is less pronounced compared to the maxillary canine.

- The mandibular central incisor has a cingulum, but it is minimal and not as robust as seen on canines.

Therefore, the maxillary canine's lingual surface exhibits the most pronounced cingulum, which helps distinguish it from other anterior teeth.

Key points:
- Cingulum: convexity on the lingual surface of anterior teeth
- Maxillary canine: most pronounced and bulky cingulum
- Function: aids occlusion and tearing, important anatomical landmark

Reference: Wheeler’s Dental Anatomy, Physiology and Occlusion, 10th Edition, Chapter 11 / Page 148