The correct answer is letter b.
The excerpt is written in the Simple Past and narrates a series of events that happened in a sequence.
Notice the verbs in the Simple Past : wept, wailed, fell, faded and died.
There is a verb missing in the part " the earth stiff and cold" The verb is grow, the Simple Past form is grew, therefore " the earth grew stiff and cold" is the correct way.
Letter A is wrong because there's a verb missing.
Letter C and letter D " the earth was growing stiff and cold" the verb grow is in the Past Continuos, " the leaves were falling from the sorrowing trees" the verb fall is also in the Past Continous breaking the pattern stablished.
The best answer here is choice B. We can determine this because of the tense used throughout the passage itself. Bearing this in mind, choice B matches the tense perfectly.
Choice A does not work at all because the verb "am" makes no sense in the context of the sentence. The same is true for choice C. The passage is not in present tense, so it cannot be this choice. Choice D could make sense, except that this is in the future tense versus the past tense.
Not c , not d , a or b <3