Final answer:
The Transverse plane is the plane that horizontally divides the body into superior (upper) and inferior (lower) portions, also known as cross sections.
Step-by-step explanation:
The term 'Transverse plane' refers to the plane that divides the body or organ horizontally into upper and lower portions. When we talk about transverse planes, we mean images that are often described as cross sections. This is contrary to the other anatomical planes such as the frontal plane, which divides the body into an anterior and a posterior portion, and the sagittal plane, which divides the body vertically into right and left sides. In the context of the multiple-choice question presented, the correct answer is the first one: 'A plane that divides the body into superior and inferior portions'.