The correct answer is: None of these.
Lord Vishnu is one of the principal deities of Hinduism. He is the preserver and protector of the universe. He is often depicted as a blue-skinned man with four arms, holding a conch shell, a discus, a mace, and a lotus flower.
Lord Vishnu is said to have taken many holy baths in his lifetime. Some of the most famous of these baths are the ones he took in the Ganges River, the Yamuna River, and the Kaveri River.
However, he is not known to have taken a holy bath in any of the places mentioned in the question.
A. Baunsi is a town in the Indian state of Bihar. It is located on the banks of the Ganges River.
B. Simaria is a town in the Indian state of Jharkhand. It is located on the banks of the Damodar River.
C. Sitamarhi is a town in the Indian state of Bihar. It is located on the banks of the Son River.
None of these places are known to be associated with Lord Vishnu.