The correct answer is: A. West Champaran.
Canebrakes are found in the Terai region of India, which is located in the foothills of the Himalayas. The Terai is a humid subtropical region with a long rainy season. Canebrakes are dense thickets of tall grasses and reeds, and they are an important habitat for many animals, including tigers, elephants, and rhinoceroses.
West Champaran is a district in the Indian state of Bihar. It is located in the Terai region, and it is one of the most important sugarcane-producing districts in India. Canebrakes are a common feature of the landscape in West Champaran, and they play an important role in the local economy.
The other options are incorrect because they are not located in the Terai region. Saran is a district in the Indian state of Bihar, and it is located in the Gangetic plain. Gaya is a district in the Indian state of Bihar, and it is located in the central part of the state. Nawada is a district in the Indian state of Bihar, and it is located in the south-central part of the state.