Fact Pattern 27-1A (Questions A17 and A18 Apply)

Fact Pattern 27-1A (Questions A17 and A18 apply)
Mike loses his National Bank access card.He realizes his loss the next day but waits a week to call National.Meanwhile,Opal finds and uses Mike's card to withdraw $3,000 from Mike's account.
-Refer to Fact Pattern 27-1A.When Mike receives his National statement,he demands that the bank investigate the matter and recredit his ac?count.The bank

A) has no duty to investigate.
B) must investigate and,if the dispute is not resolved within ten days,recredit Mike's account (at least until the dispute is resolved) .
C) must investigate and immediately recredit Mike's account (at least until the dispute is resolved) .
D) must investigate but need not recredit Mike's account.