Answer:
b. The belief systems originated in India.
Step-by-step explanation:
Speaker A propagates the religion of Buddhism founded by Siddhartha Gautama around 2500 years in India. At the same time, speaker D propagates about the union of atma, also known as Moksha, which is based on Hindu religion of India.
Therefore, the one similarity between the belief systems practiced by Speaker A and D is that both the belief systems originated in India. Though Hinduism is much older than Buddhism, both orginated in India and Buddhism is often believed to have been inspired by Hinduism.