<span>A. The nebula contracts and shrinks instead of expanding
</span><span>Nebula is the cloud of interstellar dust and gas that forms a star. It is collborately shaped during colliding and collapsing of the interstellar mediums this is influenced by the gravitational attraction of the atoms and particles in the entites. Hence, there are three types of nebular namely, are classical nebula, diffuse nebula, planetary nebular and supernova remnants.</span>
Answer:
C. Prescribed forest fires promoting healthy ecosystems.
Explanation:
This is because at that particular prescription,the place must have been analysed and proved that the forest fires would create more good to ecosystems than harm.
Letter C.. Hand washing prevents germs spreading from another