Answer is number 1
Oxygen O2
Ozone O3
The planets Mercury, Venus, Earth, and Mars, are called terrestrial because they have a compact, rocky surface like Earth's terra firma. The terrestrial planets are the four innermost planets in the solar system. ... Without life, most of the oxygen would soon become part of the compounds on the planet's surface.
B- yeast is used for baking things, it helps the dough rise in bread and pizzas etc
All of these are not part of the life cycle. It's man-made. Think of it in biology terms - something that's created genetically.
