In the sentence given below, a word is printed in bold. Below it, four choices are given. Pick the one which is most nearly the same in meaning as the word printed in bold and can replace it without altering the meaning of the sentence.
Instead of putting up a united front against on common enemy, the medieval states frittered away their energy in internecine warfare.
mutually destructive
baneful
pernicious
detrimental
Correct answer is A
No explanation has been provided for this answer.