The branch of dentistry which deals with the replacement of missing parts is called:

Prosthodontics is the branch of dentistry that deals with the replacement of missing parts such as teeth, which can be done through the use of dentures, bridges, or dental implants. This branch focuses on restoring the function and appearance of missing teeth and maintaining the health of the surrounding tissues. It is different from orthodontics (B) which deals with the alignment and positioning of teeth, periodontics (C) which focuses on the health and treatment of gum diseases, and endodontics (D) which deals with the treatment and management of the dental pulp and tissues inside the tooth. Therefore, A is the correct answer.