Which bond is formed by a positively charged metal ion and negatively charged nonmetal ion?

Correct Answer: A

Rationale: The correct answer is an ionic bond. An ionic bond is formed when a positively charged metal ion joins with a negatively charged nonmetal ion, resulting in a transfer of electrons. In contrast, a covalent bond involves sharing electrons between atoms rather than complete transfer. Functional groups are specific groups of atoms within molecules that determine the molecule's chemical properties. Metallic bonds occur between metal atoms where electrons are shared across a delocalized electron cloud.

Correct Answer: C

Rationale: Lamivudine belongs to the class of nucleoside reverse transcriptase inhibitors (NRTIs), making choice C the correct answer. NRTIs like lamivudine work by inhibiting the reverse transcriptase enzyme, an essential component for the HIV virus to replicate. Choices A, B, and D are incorrect because lamivudine does not function as a CCR5 antagonist, fusion inhibitor, or protease inhibitor in the management of HIV infection.

Correct Answer: B

Rationale: Anticoagulants are the most suitable choice for a patient following a myocardial infarction. These medications are essential in preventing further blood clots from forming in the arteries, reducing the risk of complications such as strokes or recurrent heart attacks. Antiemetics are used to control nausea and vomiting, not directly related to myocardial infarction. Anticonvulsants are used to manage seizures, not typically indicated after a heart attack. Antibiotics are prescribed to treat bacterial infections, not routinely given after a myocardial infarction.

Correct Answer: C

Rationale: English muffins would be the most suitable option for a patient on a fat-restricted diet. They are typically lower in fat compared to fried rice, granola, and popcorn with butter. Popcorn, fried rice, and granola are higher in fat content and may not be the best choice for individuals on a fat-restricted diet.

Correct Answer: B

Rationale: Achalasia is the correct answer. It is a condition characterized by the esophagus having difficulty moving food toward the stomach, resulting in dysphagia (difficulty swallowing). Myasthenia gravis (Choice A) is a neuromuscular disorder that affects skeletal muscles, not the esophagus. Alzheimer's disease (Choice C) primarily affects cognitive function, not the esophagus. Cerebral palsy (Choice D) is a neurological disorder affecting body movement and muscle coordination, unrelated to esophageal dysphagia.