Final answer:
A nurse would anticipate polyhydramnios in a client with class IV heart disease in her third trimester due to the body's challenged fluid management and the subsequent accumulation of excessive amniotic fluid. Option D is the correct answer.
Step-by-step explanation:
When considering a client with class IV heart disease who is in her third trimester of pregnancy, the nurse would anticipate D) polyhydramnios as a potential problem. Heart conditions can exacerbate issues related to fluid management in the body during pregnancy. As a result, excessive amniotic fluid can accumulate, which is known as polyhydramnios. While maternal hypertension may also be a concern due to changes in circulatory system dynamics, the growth of the uterus and fetus mainly press upon blood vessels, potentially leading to circulatory issues in the mother's legs and possibly resulting in clots. These vascular changes, however, are more indicative of complications that arise from increased pressure on the veins and less about polyhydramnios, which is specifically tied to the volume of amniotic fluid.