Question

constellations are *
○ groups of stars that are close to one another
○ groups of stars that form recognizable patterns in the sky
○ groups of stars that are visible at all times
○ groups of stars that are the brightest in the sky

the source of a stars energy *
○ nuclear fission
○ electricity
○ fire
○ nuclear fusion

Explanation:

First Question (Constellations are):

Constellations are defined as groups of stars that form recognizable patterns in the sky. Stars in a constellation may not be close to each other in space (just appear that way from Earth), not all are visible at all times, and not all are the brightest. So the correct option is the one about forming recognizable patterns.

Stars generate energy through nuclear fusion, where hydrogen atoms combine to form helium, releasing energy. Nuclear fission is splitting atoms (not star energy source), electricity and fire are not star energy sources. So the correct option is nuclear fusion.

Answer:

B. groups of stars that form recognizable patterns in the sky (assuming the options are labeled A, B, C, D with B as the selected one here)

Second Question (The source of a star's energy):