The best answer would be A. pre: first
"Sweating in the heat, we had lost the whole day, dreading to be buried alive in the drifting sand." & <span>"Sand in the scanty food, sand in the brackish water—water that was drunk lukewarm from a clammy, loathsome water-skin."</span>
C, She is coming, as a result to the dinner party.
Concept checking is the process of a teacher asking questions to their students to make sure they understand the vocabulary/grammar you have taught them. =)