I really don’t care I just want free points
The phrase "for more than 100 years" is an adverbial phrase that denotes a time and is therefore known also as a temporal adverbial phrase.
Another example of an adverb phrase would be:
"Before electricity", people had to use candles.
Before electricity is an adverbial phrase that shows when something occurred.
Answer: Palpable.
The word "palpable" has the idea of something that can be felt. The boys were in fear of something, therefore palpable makes the most sense rather than the other choices.
