Correct Answer: A

Rationale: Multifactorial problems are conditions that result from the interplay of genetic and environmental factors. These conditions, such as diabetes or heart disease, are not solely determined by genetics or environment but are influenced by a combination of both factors. Choice B, cognitive problems, refers to difficulties related to thinking, learning, and memory and are not specifically linked to genetic and environmental interactions. Choices C and D, horizon problems and coronal problems, are nonsensical terms and do not relate to the interaction of heredity and environmental factors.

Correct Answer: A

Rationale: Nagele's Rule is a common method used to estimate the due date. To calculate it, subtract 3 months and add 7 days to the first day of the last menstrual period. In this case, if the last menstrual period started on July 10, subtracting 3 months (April) and adding 7 days gives an estimated due date of April 17. This is the correct answer. Choices B, C, and D are incorrect because they do not follow the Nagele's Rule calculation method.

Correct Answer: D

Rationale: The correct answer is Monozygotic (MZ) twins. Monozygotic twins, also known as identical twins, share 100% of their genes because they originate from the same fertilized egg that splits into two. Fraternal twins (choice B), also known as dizygotic (DZ) twins (choice C), result from two separate fertilized eggs and share approximately 50% of their genes. Biovular twins (choice A) is not a term used in genetics and does not describe a type of twinning.

Correct Answer: A

Rationale: The correct answer is 'allele.' An allele refers to one of two or more versions of a gene located at the same position on a chromosome. In genetics, alleles are responsible for variations in inherited traits. Choice B, 'zygote,' is incorrect as a zygote is a fertilized egg cell formed by the fusion of two gametes. Choice C, 'autosome,' is incorrect as autosomes are non-sex chromosomes that determine an individual's genetic traits excluding sex-linked characteristics. Choice D, 'node,' is incorrect as it does not relate to the concept of genes or genetic inheritance.

Correct Answer: A

Rationale: At 14 weeks of gestation, the uterus is still relatively low in the abdomen. Placing the Doppler midline 2 to 3 cm above the symphysis pubis is appropriate for assessing the fetal heart rate. This location allows for better detection of the fetal heart tones as the uterus is at a lower position during this stage of pregnancy. Placing the Doppler on the left upper abdomen would not be ideal at 14 weeks gestation as the uterus is not yet at that level. Placing it two fingerbreadths above the umbilicus or lateral at the xiphoid process would also not be accurate for locating the fetal heart rate at this stage of gestation.