**Core Concept:** Theophylline is a bronchodilator and phosphodiesterase inhibitor used to treat asthma, chronic obstructive pulmonary disease (COPD), and other respiratory conditions. It acts by increasing intracellular cyclic AMP levels, leading to relaxation of bronchial smooth muscles and reduction in bronchoconstriction.

**Why the Correct Answer is Right:** The correct answer, option A, states that theophylline levels in blood are increased by administering more of the drug. In clinical practice, this can be achieved by adjusting the dosage or frequency of theophylline administration, such as increasing the dose or administering the drug more frequently. Increased theophylline levels are beneficial because they lead to more effective bronchodilation and relief of respiratory symptoms.

**Why Each Wrong Option is Incorrect:**

Option B is incorrect because it mentions "increased renal blood flow." While this is a potential side effect of theophylline, it is not an accurate way to increase blood levels of the drug.

Option C incorrectly states that theophylline levels are increased by increasing the rate of respiration. While increased respiration can improve oxygenation and benefit the patient, it does not directly influence theophylline blood levels.

Option D is incorrect as it mentions "increased absorption." While the rate of absorption can impact theophylline levels, the main factor that determines blood levels is the administered dose and frequency, as mentioned in option A.

**Clinical Pearl / High-Yield Fact:** Theophylline levels should be monitored regularly, especially in patients with altered renal function or when adjusting dosage. Monitoring ensures therapeutic drug levels are achieved, preventing toxicity and maintaining optimal treatment outcomes.