Question

read the passage from sugar changed the world. a stream of pale ash - colored syrup gushed out from the mills, bubbling white with foam. the liquid rushed down a wooden gutter directly into the boiling house, a building of massive furnaces and cauldrons, where the syrup was heated and strained and turned into crystals. a giant copper kettle—often about four feet across and three feet deep—waited for the pale river. this was the first in a series of ever - smaller cauldrons, and beneath each gaped what the brazilians called the “great open mouths”—the huge furnaces that had to be constantly filled with the wood that workers had chopped down and hauled to be ready for this moment. the boiling house was as perilous as the mills, for if a person nodded off for a second, he or she could slip into a bubbling vat. mammoth fires burned in the “mouths,” clouds of steam billowed above the kettles, and the heat was so intense that the boiling houses had to be sprayed with water so they would not go up in flames. then there was the smell, or rather, the stench of the boiling liquid. as the sugar cane juice boiled, a foul scum rose to the top—which a slave had which text evidence best supports the authors’ claim that sugar processing was a long and difficult process? “a stream of pale ash - colored syrup gushed out from the mills.” “then there was the smell, or rather, the stench of the boiling liquid.” “as the sugar cane juice boiled, a foul scum rose to the top.” “over and over again the liquid had to be strained and purified.”

Explanation:

• The phrase "Over and over again the liquid had to be strained and purified" indicates repetition, which implies a long - drawn - out process. Straining and purifying multiple times is consistent with a difficult and lengthy procedure.
• The first option just describes the syrup coming out of the mills, which is a single action and does not imply a long process.
• The second option about the smell does not relate to the length or difficulty of the process.
• The third option about the scum rising is a part of the boiling process but does not emphasize the length or repetition of the overall sugar - processing.

Answer:

"Over and over again the liquid had to be strained and purified."