Explanation:
Nuclear fusion is a process in which two small nuclei combine together to result in the formation of a larger nuclei.
In Sun, the first step of hydrogen fusion includes combining of two hydrogen nuclei to result in the formation of a deuterium, positron and neutrino.
The nuclear fusion reaction inside the sun is as follows.
Thus, we can conclude that products of step 1 of the hydrogen fusion process in the Sun are isotope of hydrogen, a neutrino, and a positron.