From the sum of 2y^2 + 3yz, – y^2 – yz – z^2 and yz + 2z^2, subtract the sum of 3y^2 – z^2 and –y^2+ yz + z^2

Question

( A ) – y^2 - 2yz - z^2
( B ) – y^2 + 2yz
( C ) None of these
( D ) – y^2 + 2yz + z^2