As per Soyka et al. (2011) , Opiates impair cognitive functioning in the following areas:

A) frontal cortex
B) cerebellum
C) hippocampus
D) both a and c

Frontal Cortex

The front part of the cerebral cortex involved in decision making, problem solving, control of purposeful behaviors, consciousness, and emotions.

Cerebellum

A part of the brain located at the back of the skull, primarily involved in coordinating movement and balance.

Hippocampus

A major component of the brain that plays critical roles in memory formation, navigation, and the emotional response.