Final answer:
In anatomical terms, the back is considered 'posterior' to the chest, which is 'anterior' or 'ventral'. The correct answer is C. posterior.
Step-by-step explanation:
In relation to the chest, the back is posterior. This term describes the back or direction toward the back of the body. The chest, being at the front of the body, is described as ventral or anterior. Hence, the correct answer to the question is C. posterior. In anatomical positions, ventral refers to the anterior or front of the body, while the dorsal side refers to the back or posterior part of the body. The ventral cavity includes the thoracic cavity and the abdominopelvic cavity, which are anterior to the dorsal cavity holding the brain and spinal cord.