This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General pharmacology, Subject name: Pharmacology
Which of the following statements best describes long-acting nitrate preparations? 
Select and explain. 
A. Tolerance often develops, B. Their effect can be blocked by high doses of beta selective inhibitors, C. Trasdermal patches are more likely to be associated with headaches than are sublingual nitrates, D. Oral preparations are more effective than sublingual ones
A: Tolerance often develops
Answer: A: Tolerance often develops 
Explanation: Nitrates are generalized smooth-muscle dilators whose direct effect on the vasculature cannot be blocked by any currently available agents. Long-acting preparations of nitroglycerin may be completely degraded by the liver in some patients and thus are generally less effective than sublingual forms. Because individual variability in metabolism is considerable, doses should be titrated against side effects and should not conform to a rigidly standardized regimen. Tolerance is common and must be considered if a patient fails to respond to a previously efficacious dose. Long-acting preparations such as transdermal patches are less likely to produce the nitrate-associated side effects of headaches and dizziness that are the more rapidly acting sublingual forms. Ref: katzung 12th ed.