0#1-- 'b' is not possible because present perfect 'hasn't done' indicates that 'doing something' is still possible, a bit of illogic for this police investigation of a past crime. 02br 02br 00#2-- 'a' is wrong because it need not be carried over ('must' is wrong). 02br 02br 00#3-- 'commitments with' is an incorrect collocation, so 'c' is wrong.
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