A.capricious=given to sudden and unaccountable changes of mood or behaviour;unpredictable
B.considered=think carefully about (something), typically before making a decision;look attentively at
C.malicious=characterized by malice; intending or intended to do harm
D.pessimistic=tending to see the worst aspect of things or believe that the worst will happen
E.insidious=proceeding in a gradual, subtle way, but with very harmful effects.
F.erratic=not even or regular in pattern or movement; unpredictable
So,Answer would be (A,F)

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