Correct Answer: B

Rationale: Individuals with Klinefelter syndrome have an extra X chromosome (XXY), leading to reduced production of testosterone, the primary male sex hormone. This deficiency can result in various physical and developmental characteristics associated with the syndrome. Estrogen levels may actually be relatively elevated due to the imbalance between testosterone and estrogen. Choices C and D are incorrect as adenine and thymine are nucleotide bases found in DNA and are not related to hormone production.

Correct Answer: D

Rationale: In pregnant women with cardiac problems, signs of cardiac decompensation include dyspnea, crackles, an irregular, weak, and rapid pulse, rapid respirations, a moist and frequent cough, generalized edema, increasing fatigue, and cyanosis of the lips and nailbeds. Choice A is incorrect as a regular heart rate and hypertension are not typically associated with cardiac decompensation. Choice B is incorrect as increased urinary output and dry cough are not indicative of cardiac decompensation, only tachycardia is. Choice C is incorrect as bradycardia and hypertension are not typically seen in cardiac decompensation; dyspnea is a critical sign instead.

Correct Answer: C

Rationale: The correct response is C because the nonstress test is specifically used to assess the baby's well-being close to the due date. It helps determine if the baby is receiving enough oxygen and nutrients in the womb. Choice A is incorrect as the test does not assess the mother's stress level but focuses on fetal well-being. Choice B is incorrect as the test does not predict the baby's ability to withstand labor. Choice D is incorrect because the test does not solely indicate if the baby needs to be delivered to avoid a bad outcome; rather, it assesses the current well-being of the baby.

Correct Answer: A

Rationale: The correct answer is A: codominance. Codominance refers to a genetic scenario where both alleles in a gene pair are fully expressed, leading to a phenotype that displays traits from both alleles equally. This is distinct from incomplete dominance where the traits blend. Choices B, C, and D are incorrect. Preponderance does not specifically relate to the expression of alleles. Ascendance and concurrence do not describe the genetic concept of codominance where both alleles are fully expressed.

Correct Answer: A

Rationale: Androgens are male sex hormones, such as testosterone, produced by the testes after they have developed in the embryo. Androgens are responsible for the development of male secondary sexual characteristics. Genotypes refer to an individual's genetic makeup, not hormones. Blastocysts are early stage embryos, not male sex hormones. Teratogens are substances that can interfere with fetal development, not male sex hormones produced by the testes.