If \[a=7,\] then the value of \[-\left( \frac{1-2a}{a-5} \right)\] is____.

• A.  \[-\frac{13}{2}\]                   
• B.  \[-\frac{15}{2}\]                   
• C.  \[\frac{13}{2}\]                                 
• D.  \[\frac{15}{2}\]