Problem: OPTIONS:
- oxygen
- base
- carbon
- acid
Q: Q: What causes blue litmus to turn red? A:
Answer: acid

Problem:OPTIONS:
- nuclides
- nutrients
- antibiotics
- steroids

Q: Sterols are a subgroup of what? A:
****
A: steroids

Q: What causes the changes of puberty? A:
OPTIONS:
- glucose
- insulin
- testosterone
- estrogen
estrogen

Q: What is used during filtration to push fluids and solutes, from higher pressure areas to lower pressure areas? A:
OPTIONS:
- constructs pressure gradient
- limited pressure gradient
- magnesium pressure gradient
- hydrostatic pressure gradient

Answer: hydrostatic pressure gradient

Question: Q: Metals, fossil fuels, and water are all examples of what type of resource? A:
OPTIONS:
- ores
- recyclables
- renewable resources
- natural resources
Answer: natural resources

input: OPTIONS:
- meteor shower
- Coriolis effect
- aurora nervosa
- northern lights Now, answer this question: Q: What colorful phenomenon occurs in the northern sky when particles from the sun energize ions in the thermosphere? A:
A:
output:
northern lights