The correct answer is option 'C' - Brain.

- The brain is the part of our body that controls all the activities. It is often referred to as the control center of the body.
- The brain is located inside the skull and is protected by the skull bones.
- It is made up of billions of nerve cells called neurons, which are responsible for transmitting electrical signals and communicating with each other.
- The brain controls all the functions of our body, including our thoughts, emotions, actions, and bodily functions.
- It receives information from our senses (such as sight, hearing, taste, smell, and touch) and processes this information to make sense of the world around us.
- The brain also controls voluntary movements, such as walking, talking, and writing, as well as involuntary actions, such as heartbeat, breathing, and digestion.
- It is divided into different regions, each responsible for specific functions. For example, the frontal lobe is involved in decision-making and problem-solving, while the occipital lobe is responsible for processing visual information.
- The brain is also responsible for our memory, learning, and language skills.
- It is a highly complex organ and continues to develop and change throughout our lives.
- Any damage or dysfunction in the brain can have significant effects on our overall health and well-being.

In conclusion, the brain is the part of our body that controls all the activities. It is responsible for processing information, coordinating bodily functions, and controlling our thoughts and actions.