Final answer:
The Japanese religion that beliefs in the presence of ancestors in the air around them is Shinto.
Step-by-step explanation:
The Japanese religion that is still practiced today and includes a belief that people's ancestors are present in the air around them is Shinto (a). Shintoism is an ethnic religion of Japan focusing on ritual practices to establish a connection between present-day Japan and its ancient past. It venerates ancestors and the divine forces of nature, recognizing spirits known as kami that exist in plants, animals, rocks, places, and sometimes people. As the indigenous religion of Japan, Shintoism holds that many gods and spirits are to be revered and honored, and this includes the spirits of former rulers and chieftains, such as ancestors.