False sensory perceptions that often take the form of hearing voices are called a. delusions b. hallucinations c. obsessions d. compulsions

Option B, Hallucinations

Explanation:

Hallucination causes sensory perceptions in the absence of any external stimuli and hence these sensations are termed as false sensory perceptions. False sensations feel like extraordinarily natural and are different from delusion as they occur under sensory modality.  

They are extremely different from illusion where a person perceive a different scenario for an existing scenario while in case of hallucination a person perceives a scenario even when it do not exists.  

Hence, option B is correct