What do we get after expanding (p+3q-2z)2?

• A. p2 + 9q2 + 4z2 + 6pq – 12qz + 4zp
• B. p2 + 9q2 + 4z2 + 12pq + 12qz + 4zp
• C. p2 + 9q2 + 4z2 – 12pq – 12qz – 4zp
• D. p2 + 9q2 + 4z2 + 6pq – 12qz – 4zp