The correct option is A 8a2−3b2−10xy−7
Let the term to be added be 's' .
3xy−4a2+5b2+2+s=−5+4a2+2b2−7xy
⇒s=(−5+4a2+2b2−7xy)−(3xy−4a2+5b2+2)
Rearranging the terms and subtracting,
4a2+2b2−7xy−5
−4a2+5b2+3xy+2
(+) (-) (-) (-)
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8a2−3b2−10xy−7