The largest part of the brain is which of the following?

The cerebrum is the largest part of the brain, making it the correct answer. It comprises about 85% of the brain's total weight and is located in the uppermost region of the brain. The cerebrum is responsible for various higher brain functions, including thought, action, reasoning, and sensory perception. It is divided into two hemispheres and further subdivided into lobes, which are involved in different functions.

In contrast, the parietal lobe, while significant for processing sensory information, is just one part of the cerebrum and does not encompass the entire structure. The cerebellum, which is located beneath the cerebrum at the back of the brain, plays a crucial role in coordination and balance but is much smaller than the cerebrum. The frontal lobe, also part of the cerebrum, is vital for decision-making and problem-solving, but it is still only a fraction of the entire cerebrum. This hierarchical structure and function of the brain regions clarify why the cerebrum is considered the largest part.