Route of administration of alendronate is:

Correct Answer: C

Rationale: The correct answer is C: Oral. Alendronate is typically administered orally as it is a bisphosphonate used in the treatment of osteoporosis. The oral route ensures optimal absorption in the gastrointestinal tract. Intravenous and subcutaneous routes are not commonly used for alendronate due to potential adverse effects and practicality issues. Intranasal route is not a common administration method for alendronate. In summary, the oral route is preferred for alendronate administration due to its efficacy, safety, and convenience compared to other routes.

Correct Answer: C

Rationale: Cephalosporins are broad-spectrum antibiotics effective against both gram-positive and gram-negative bacteria. They are commonly used when penicillins are ineffective. This makes choice C the correct answer, as it accurately reflects the versatility and effectiveness of cephalosporins. A: Gram-positive microorganisms - Incorrect. Cephalosporins are effective against both gram-positive and gram-negative bacteria. B: Gram-negative microorganisms - Incorrect. Cephalosporins are effective against both gram-positive and gram-negative bacteria. D: Only bacteroide infections - Incorrect. Cephalosporins are effective against a wide range of bacteria, not limited to just bacteroide infections.

Correct Answer: B

Rationale: Step 1: Quinolone derivatives are a class of antibiotics that target bacterial DNA synthesis. Step 2: Nalidixic acid is a first-generation quinolone derivative that inhibits DNA gyrase enzyme. Step 3: Nalidixic acid is effective against gram-negative bacteria, making it an antibacterial drug. Step 4: Nitrofurantoin is a nitrofuran antibiotic, not a quinolone derivative. Step 5: Streptomycin is an aminoglycoside antibiotic that inhibits protein synthesis, not DNA synthesis. Step 6: Metronidazole is an antimicrobial drug used for anaerobic bacteria and protozoa, not a quinolone derivative.

Correct Answer: C

Rationale: Step-by-step rationale: 1. Saquinavir is a protease inhibitor used in the treatment of HIV by blocking viral proteases essential for viral replication. 2. Rimantadine is an antiviral drug used for influenza A virus, not inhibiting viral proteases. 3. Acyclovir is an antiviral drug for herpes simplex virus, working by inhibiting viral DNA synthesis, not proteases. 4. Zalcitabine is a nucleoside analog used for HIV, but it inhibits reverse transcriptase, not viral proteases. Summary: Saquinavir is the correct answer as it specifically inhibits viral proteases crucial for viral replication. The other choices target different viral enzymes or processes, making them incorrect for this question.

Correct Answer: C

Rationale: The correct answer is C: Nitroglycerin. Nitroglycerin is a vasodilator that works by releasing nitric oxide, which leads to decreased platelet aggregation. This helps improve blood flow and reduce symptoms like chest pain in patients with heart conditions. Propranolol (A) is a beta-blocker that doesn't directly affect platelet aggregation. Isosorbide mononitrate (B) is a vasodilator but doesn't have a significant impact on platelet aggregation. Nifedipine (D) is a calcium channel blocker that also doesn't directly influence platelet aggregation.