Which of the following is/are controlled by the human brain ?
a. Balance of the body
b. Circadian rhythm of the body
c. Human behaviour
d. Functioning of heart and kidneys

Options

A. Only d
B. a and d
C. a, b and c
D. a, b , c, d

Answer

To determine which of the following options are controlled by the human brain, we will analyze each option step by step:

### Step-by-Step Solution:

1. **Option A: Balance of the body**
- The balance of the body is primarily controlled by the vestibular system located in the inner ear. However, the brain processes the information received from the vestibular system to maintain balance. Therefore, the brain plays a crucial role in maintaining body balance.

2. **Option B: Circadian rhythm of the body**
- The circadian rhythm, which regulates sleep-wake cycles and other physiological processes, is controlled by the brain, specifically by the suprachiasmatic nucleus (SCN) located in the hypothalamus. This nucleus responds to light and dark signals, helping to regulate the body's internal clock.

3. **Option C: Human behavior**
- Human behavior is largely influenced by the brain. Different areas of the brain are responsible for various aspects of behavior, including decision-making, emotions, and social interactions. Thus, the brain is a key player in controlling human behavior.

4. **Option D: Functioning of heart and kidneys**
- While the heart and kidneys have their own intrinsic functions, their activities are regulated by the autonomic nervous system, which is controlled by the brain. The brain sends signals to these organs to regulate heart rate, blood pressure, and kidney function, thus playing a significant role in their functioning.

### Conclusion:
Based on the analysis of each option, all the options (A, B, C, and D) are controlled by the human brain. Therefore, the correct answer is that all of the above are controlled by the human brain.

### Final Answer:
**All of the options (A, B, C, D) are controlled by the human brain.**

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