Final answer:
The first-line treatment for a mute catatonic patient in the emergency room is Lorazepam, which is effective in reducing catatonic symptoms. Antipsychotics are generally not used as the initial treatment due to the risk of exacerbating the condition.
Step-by-step explanation:
The first-line treatment for a mute catatonic patient who is brought into the emergency room is D. Lorazepam. Catatonia is a psychomotor syndrome that can present with a variety of psychiatric or medical conditions. Benzodiazepines, like lorazepam, are typically the first choice for immediate treatment due to their efficacy in reducing catatonic symptoms. While antipsychotics, such as haloperidol and risperidone, are used in the treatment of schizophrenia and other psychotic disorders, they are not the usual first step for catatonic symptoms as they may exacerbate the condition or have severe side effects. If benzodiazepines are ineffective, other treatments such as electroconvulsive therapy (ECT) might be considered.