Question

the horseshoe crabs name may be a bit bewildering, as these marine animals have nothing to do with horses—and they arent even crabs! the horseshoe crab is closely related to spiders and scorpions. this animals name comes from its smooth, hard shell thats shaped like a horseshoe. some call horseshoe crabs the dinosaurs of the ocean because these critters have been around for 450 million years. yet, while dinosaurs came and went over time, horseshoe crabs stuck around. in fact, their physical structure hasnt evolved in all these many, many years. living fossils indeed!
there are four species of horseshoe crabs, but only one can be found in coastal waters off the united states. atlantic horseshoe crabs inhabit ocean waters from northern maine to florida, making an appearance on land each spring to breed and lay eggs. their annual emergence is quite a spectacle in areas like delaware bay, delaware, where onlookers gather to witness these natural wonders come ashore. sometime from late may to early june—when the moon is full or new and the tide is high—hundreds of thousands of horseshoe crabs turn up in the surf. the female horseshoe crabs dig nests in the sand, where they deposit and bury clusters of tiny blue - green eggs—each crab can lay up to 4,000 eggs at a time! not only that, shell do this many times over, laying as many as 20,000 eggs or more in one night!
question 3
based on the article, which is true about horseshoe crabs?
a. they make nests in the water.
b. they have soft shells.
c. they
d. they have blue blood.

Explanation:

• Option A: The article says female horseshoe crabs dig nests in the sand (on land), not in water.
• Option B: The article states they have a smooth, hard shell, not soft.
• Option C: The article mentions they come ashore (not travel north) each spring to breed.
• Option D: The eggs are blue - green, and it is a known biological fact (common knowledge related to horseshoe crabs in biology) that their blood is blue (due to hemocyanin which contains copper).

Answer:

D. They have blue blood.