Answer:
utterly bewilder or perplex (someone).
make obscure or mysterious.
hope this helps

If two similar waves are traveling in the same medium, then they have same wave velocity. so we can infer that

Now, as per the formula ~ we know that :

Now, we can write it as :

And it's also given that frequency of wave A is 3 times that of frequency of wave B.
So, let's add the relation to our equation ~



So, choice C is correct ~
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