The _____ is the inner layer of the embryo from which the lungs and digestive system develop.

Correct Answer: C

Rationale: The endoderm is the correct answer. It is the innermost layer of the embryo that gives rise to organs such as the lungs, digestive system, liver, and pancreas. The neural tube (Choice A) forms the brain and spinal cord, not the lungs or digestive system. Mesoderm (Choice B) develops into structures like muscles, bones, and circulatory system, not the lungs or digestive system. The umbilical cord (Choice D) serves as a connection between the embryo and the placenta, providing nutrients and oxygen, but it is not the layer from which lungs and digestive system develop.

Correct Answer: C

Rationale: Nasal stuffiness is a common symptom during pregnancy due to increased blood flow and hormonal changes. This symptom is caused by the increased blood volume and hormonal changes that lead to swelling of the nasal passages. Choices A, B, and D are incorrect. Stomach emptying rate does not significantly change during pregnancy; the uterus does not double in size at 24 weeks but rather grows steadily, and nipples typically darken in color due to increased pigmentation.

Correct Answer: B

Rationale: The correct answer is B: 'This test will determine the adequacy of placental perfusion.' The non-stress test is used to assess fetal well-being by monitoring the fetal heart rate in response to its own movements. It helps determine if the fetus is receiving enough oxygen and nutrients through placental perfusion. Choice A is incorrect because confirming fetal lung maturity is typically determined through tests like amniocentesis, not the non-stress test. Choice C is incorrect because detecting fetal infection is not the primary purpose of a non-stress test. Choice D is incorrect because predicting maternal readiness for labor is not the purpose of the non-stress test; it focuses on fetal well-being.

Correct Answer: C

Rationale: Cystic fibrosis is a genetic disorder caused by inheriting two copies of a recessive gene, one from each parent. This means that both parents must carry at least one copy of the faulty gene for a child to inherit the condition. Choice A is incorrect because cystic fibrosis is not linked to the sex chromosomes. Choice B is incorrect as cystic fibrosis is not caused by an abnormality in the 21st pair of chromosomes but by a specific gene mutation. Choice D is also incorrect as cystic fibrosis is not related to the Y chromosome, which is specific to males.

Correct Answer: D

Rationale: The correct answer is D: 1 cup of cooked broccoli. Broccoli is an excellent source of calcium, making it a suitable choice for a vegan diet. Avocado (Choice A), banana (Choice B), and potato (Choice C) are not significant sources of calcium compared to broccoli. Avocado and banana are primarily sources of other nutrients like healthy fats and potassium, respectively. Potato is a good source of vitamin C and potassium but not calcium. Therefore, for a pregnant client following a vegan diet and seeking calcium-rich foods, cooked broccoli is the most appropriate choice.