Because the desert air was very dry, the bread became stale very rapidly. 13. In this sentence, what clue word best tells you that a cause is producing an effect?
a. Became
b. Desert
c. Very
d. Because
Option D is correct here, i.e. the word 'because' is the best answer. As
the word in essence indicates that one state or thing is effectively
bringing about a change on another is being the cause.