Q: Cells pretty much al share this one characteristic:
Options:
- (A) sensory neurons
- (B) voltage
- (C) aerobic capacity
- (D) microscopic
- (E) eukaryotic
- (F) bacteria
- (G) prokaryotic
- (H) layers of fat
A: So, my chain of thought: Cells vary in size as well as shape, but all cells are very small. All cells are microscopic in size. Cells can vary in shape, but they are all microscopic. The answer is (D).

Q: Bottleneck effect can be a precursor to what?
Options:
- (A) massive damage
- (B) Climate change
- (C) Destroy bridges
- (D) Cambrian explosion
- (E) ground to shake
- (F) clams
- (G) soda
- (H) extinction
A: So, my chain of thought: Bottleneck effect occurs when a population suddenly gets much smaller. Population size is the predictor of extinction probability. Bottleneck effect can be a precursor to extinction. The answer is (H).

Q: Mussels have what?
Options:
- (A) seaweed
- (B) arms
- (C) Energy
- (D) a shell
- (E) warmth
- (F) bacteria
- (G) Length
- (H) legs
A:
So, my chain of thought: Most mollusks have shells. Mussels are bivalve mollusks. Mussels have shells. The answer is (D).