Final answer:
Leptin is produced by adipocytes in adipose tissue and is proportional to body fat amount. Leptin resistance in obesity causes an inability to sense satiety, leading to overeating.
Step-by-step explanation:
The hormone leptin is produced by adipose tissue, which is commonly known as fat tissue. Statement C accurately describes leptin production and its relation to obesity: Leptin is produced by adipocytes and is directly proportional to the total amount of fat in the body. As the body's adipose tissue increases, it leads to higher levels of leptin, which typically should result in a decreased appetite by promoting a feeling of satiety. However, in obesity, a phenomenon known as leptin resistance can occur, where despite high levels of leptin, the body's sensitivity to this hormone is decreased. This results in an inability to detect satiety effectively, leading to continual overeating and further weight gain.