Answer:
The connotation of the word perilous affects the tone of the paragraph as A: It gives it a more adventurous tone.
Explanation:
Perilous means something that is risky or dangerous. If dangerous is replaced with perilous in the given sentence, it would add more adventurous tone to the sentence.
The sentence would mean that before the next level of training began, author had sent a risky or a very dangerous task to know their mettle or ability. It will not give the sentence down to earth or focused or scholarly tone as per other options. The sentence would go according to the meaning of the word ‘perilous’.