Which part of the brain is the largest?

The largest part of the brain is the cerebrum. It constitutes approximately 85% of the brain's total weight and is responsible for various higher brain functions. This includes cognitive tasks such as thinking, learning, memory, and the processing of sensory information. The cerebrum is divided into two halves, known as the right and left hemispheres, each of which is further divided into four lobes: frontal, parietal, temporal, and occipital. These lobes have specific roles in managing movement, speech, vision, hearing, and problem-solving.

The other options represent important parts of the brain but are not as large or as complex as the cerebrum. The cerebellum, for instance, is responsible for coordination and balance but is significantly smaller than the cerebrum. The brainstem manages basic life functions like breathing and heart rate, while the hypothalamus plays a crucial role in hormonal regulation and homeostasis. Each of these structures serves vital functions, but the cerebrum's size and extensive capabilities underscore its role as the primary center for higher brain activity.