Question

1. what is the birthplace and start of the life cycle of a star?

nebula
main sequence star
supernova
black hole

Explanation:

Stars form from clouds of gas and dust called nebulas. Gravity causes the material in the nebula to collapse and heat up, starting the star - formation process. Main - sequence stars are in the stable phase of a star's life, supernovas are the explosive end - stages, and black holes can form from the remnants of massive stars.

Answer:

Nebula