Question

read the passage. pearls are valuable gems made by mollusks, a group that includes oysters, clams, and mussels. when a foreign object, like a parasite, enters its shell, the mollusk protects itself by coating the intruder with a smooth, shiny substance called nacre, also known as mother of pearl. layer by layer, the nacre builds up to form a pearl. in the past, most pearls were found by divers searching the seas, but natural pearls are now exceedingly rare. today, most pearls are cultured, meaning they are grown with human help. pearl farmers insert a small bead made of shell into a mollusk, then place it back into the ocean or a freshwater lake. after two to five years, the mollusks layers of nacre create a beautiful pearl, ready to be harvested. based on clues in the passage, what is most likely true about pearls? mollusks make natural pearls, but farmers do not use mollusks for cultured ones. all sea creatures with shells can make pearls from parasites that get stuck inside. pearl farmers have to plan far in advance for a successful cultured pearl harvest. farm - grown pearls are not made of nacre because that process takes too long.

Explanation:

The passage states that pearl farmers insert a bead into a mollusk and then wait two - five years for the pearl to form. This implies long - term planning for a successful harvest. Option 1 is incorrect as farmers use mollusks for cultured pearls. Option 2 is too broad; only mollusks among shelled sea creatures can make pearls as described. Option 4 is wrong since both natural and cultured pearls are made of nacre.

Answer:

Pearl farmers have to plan far in advance for a successful cultured pearl harvest.