Evaluate the expression \[81\text{ }{{p}^{2}}+16{{q}^{2}}-72pq\]when \[p=\frac{2}{3}\]. and \[q=\frac{3}{4}\] .

• A.  \[-16\]          
• B.  \[9\]         
• C.         \[-9\]        
• D.         \[16\]