An individual's phenotype reflects both genetic and environmental influences.

Correct Answer: A

Rationale: The correct answer is A: phenotype. A phenotype is the observable characteristics of an individual, which result from the interaction of their genotype with the environment. This interaction between genetics and the environment determines how genes are expressed and how traits are manifested in an individual. Choices B, C, and D are incorrect because chromosomes, alleles, and genotypes are components of an individual's genetic makeup, but they do not directly reflect the observable traits influenced by both genetics and the environment.

Correct Answer: B

Rationale: The correct answer is B: "Breast milk can be stored in a deep freezer for 12 months." This instruction is important for mothers returning to work to ensure a long-term storage option for breast milk. Choice A is incorrect because thawed breast milk should be used within 24 hours if stored in the refrigerator. Choice C is incorrect as breast milk can be kept at room temperature for only up to 4 hours. Choice D is incorrect as thawed breast milk that is unused should not be refrozen due to safety concerns.

Correct Answer: A

Rationale: Before meiosis, a sperm cell contains 46 chromosomes. This is because sperm cells, like other somatic cells, have a diploid number of chromosomes. During meiosis, the number of chromosomes is halved to 23 to combine with an egg cell during fertilization. Choice B is incorrect because a sperm cell carries either an X or a Y chromosome, not both (Choice D). Choice C is incorrect as sperm cells are generally smaller than egg cells, which is an adaptation that aids in motility and penetration of the egg during fertilization.

Correct Answer: B

Rationale: The correct answer is mesoderm. The mesoderm is the middle layer of the embryo that gives rise to the bones, muscles, and other connective tissues. The neural tube (choice A) develops into the nervous system, not bones and muscles. The ectoderm (choice C) forms the skin and nervous system, not bones and muscles. The umbilical cord (choice D) is a structure that connects the developing fetus to the placenta; it is not a layer of the embryo that gives rise to bones and muscles.

Correct Answer: B

Rationale: Misoprostol can be used for induction in clients with gestational diabetes mellitus. Choice A, a client with active genital herpes, is not a candidate for misoprostol induction due to the risk of viral shedding and transmission. Choice C, a client with a previous uterine incision, may be at risk for uterine rupture with misoprostol use. Choice D, a client with placenta previa, is not an appropriate candidate for misoprostol induction due to the risk of increased bleeding associated with the condition.