The correct option is B To study the Atmosphere
Aryabhata, the first satellite built by India, was launched on this day April 19, in the year 1975. Aryabhata was built by the Indian Space Research Organization (ISRO) to conduct experiments in X-ray astronomy, agronomics, and solar physics. The aim of the launching of the Aryabhatta satellite was for conducting scientific experiments for the study of the upper atmosphere.