Task: Question Answering
Input (English): Question: The main pharmacological treatment for obsessive-compulsive disorder or OCD is: 
 Options:  <1> Dopamine agonists. <2> NMDA receptor blockers. <3> Inhibitors of monoamine oxidase or MAOIs. <4> Selective serotonin or 5-HT reuptake inhibitors. <5> Neuroleptics
Output (English): 4