9. Which is a breeding method used by humans to produce new varieties of plants and animals?
A:
assortment
B:
Natural selection
C:
Article selection
D:
Crossing over

According to theories of how life began, how did early organic molecules begin to separate from the outside world? a: specialized enzymes were required b: chains of amino acids created a barrier c: formation of microspheres or vesicles d: rna catalyzed the formation of membranes