Ques and Ans: When snow falls to the ground and soaks into the ground, what can it become?
Options:
- (A) steam
- (B) ice
- (C) Sediment
- (D) thermal heat
- (E) dangerous
- (F) flooding
- (G) groundwater
- (H) rainfall
(G)
Explanation for the Ans above: [[Some precipitation that falls on land may soak into the ground, becoming groundwater. Most of the precipitation falls as snow. Some snow that falls on land may soak into the ground becoming groundwater.]]

Ques and Ans: Heavy metals are _.
Options:
- (A) emissions
- (B) dangerous
- (C) bent
- (D) homogenous
- (E) antigens
- (F) vehicles
- (G) fossil fuels
- (H) heat energy
(E)
Explanation for the Ans above: [[Antigens are molecules that the immune system recognizes as foreign to the body. Heavy metals are, in general, foreign to the body. Heavy metals are antigens.]]

Ques and Ans: These belong to the class of creature that were the first true tetrapods:
Options:
- (A) millipede
- (B) crabs
- (C) four limbs
- (D) bullfrogs
- (E) gastropod
- (F) a fish
- (G) warm-blooded
- (H) insects
(D)
Explanation for the Ans above:

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
[[Amphibians are the first true tetrapods, or vertebrates with four limbs. Bullfrogs eat other amphibians. Bullfrogs are of the class of creatures that were the first true tetrapods.]]