Critical Reasoning (CR) | In recent years, a village outside Osaka, Japan has taken to hosting a

Answer is B

Before going to choices:

take festival seriously (A) -> dress up as ninja (B) => given ---------------------------- (1)
now reverse , B -> A, (i.e) dress up ninja -> take festival seriously =>need not be true. ---------------------(2)

Now

(A) Any attendee who dresses up as a ninja takes the festival seriously.

Negate it - some attendee who dresses up as a ninja does NOT take the festival seriously.
so what, it does not destroy the argument because
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