Final answer:
The effectiveness of levodopa/carbidopa in a client can be indicated by improved motor control, such as the ability to wash one's face. This improvement suggests the medication is successfully treating Parkinson's disease symptoms, which is its primary use.
Step-by-step explanation:
The medication levodopa/carbidopa is prescribed primarily for the treatment of Parkinson's disease, which is characterized by symptoms such as tremors, rigidity, bradykinesia (slowness of movement), and postural instability. The hallmark of an effective response to levodopa/carbidopa would be an improvement in motor control, allowing the individual to perform daily activities with greater ease. Therefore, the correct answer to the question is: 'a. The client is able to wash their face.'
This outcome demonstrates regained motor skills necessary for performing fine motor activities, a direct indication that the medication is addressing the symptoms of Parkinson's disease effectively. It's important to note that levodopa/carbidopa does not typically impact seizure frequency, heartburn, or sleep patterns directly, making the other options less indicative of the medication's effectiveness for its primary use.