input with options: Q: What is the most numerous species on the planet? A:
OPTIONS:
- trees
- viruses
- humans
- bacteria
output: bacteria

input with options: Q: What term describes a drug that has an effect on the central nervous system? A:
OPTIONS:
- nonaddictive drug
- elemental drug
- steroidal drug
- psychoactive drug
output: psychoactive drug

input with options: Q: Some earthworms can also reproduce asexually by fragmentation followed by what? A:
OPTIONS:
- fertilization
- germination
- digestion
- regeneration
output: regeneration

input with options: Q: What is a species that plays an especially important role in it's community called? A:
OPTIONS:
- complement
- Invasive
- Leader
- keystone
output:
keystone