Answer:
Toward heaven, till the tree could bear no more,
Explanation:
In poetry, the term enjambment refers to the continuation of a sentence without a pause beyond the end of a line. In other words, the sentence doesn't end at the end of the verse but rather continues in the next one.
In this example, we see that in line number 2 "And climb black branches up a snow-white trunk" the sentence continues in line number 3 (as the complete sentence would be "and climb black branches up a snow-white trunk towards heaven")
Therefore, we can see that the enjambment is present in line number 3 "Toward heaven, till the tree could bear no more"
We can see that lines 4 to 6 (the other answer choices) are complete sentences by themselves so therefore, the correct answer is line number 3.
