Which lobe of the brain is primarily responsible for cognition and motor function?

The frontal lobe is primarily responsible for cognition and motor function, making it the correct choice in this context. This region of the brain is involved in a variety of higher-level functions such as reasoning, problem-solving, planning, and impulse control. It plays a crucial role in managing behaviors and emotions while also regulating voluntary motor movements and coordination. The primary motor cortex, located within the frontal lobe, is specifically responsible for the initiation and control of voluntary movements.

In contrast, the other lobes mentioned have their distinct roles: the parietal lobe primarily processes sensory information and is involved in spatial orientation, while the cerebellum is crucial for coordination, balance, and fine motor control, but not for higher cognitive functions. The occipital lobe mainly handles visual processing, focusing on the interpretation of visual stimuli rather than cognitive or motor control. Therefore, the frontal lobe is identified as the key region for cognition and motor function.