What did Frightful need to be able to migrate south?

That time of year thou mayst in me behold when yellow leaves, or none, or few do hang upon those boughs which shake against the cold, bare ruined choirs, where late the sweet birds sang in me thou sees the twilight of such day as after sunset fadeth in the west; which by and by black night doth take away, death's second self that seals up all in rest. in me thou seest the glowing of such fire that on the ashes of his youth doth lie, as the deathbed whereon it must expire, consumed with that which it was nourished by. this thou perceiv'st, which makes thy love more strong, to love that well, which thou must leave ere long. the first stanza compares the leafless limbs of a tree to a. yellow leaves b. sweet birds c. bare choirs d. summer

One way to show a character is a) to use dialogue b) use dynamic sentences c) interview friends d) share details

What is the best definition of detonation a.) the meaning of the word in a different language b.)the dictionary meaning of the word c.) the additional meaning that comes from the feeling one gets from a word d.) the meaning of irony