irule

Hi Bhupendra , 
in Step 2 of rewrite >>> do you need the source ip matches as well or Not ? 

So you need to match on specific source IP address/address first and then match /A or /B then move traffic to pool A but if the same match on source ip address/addresses but with uri starts with /c-new modify it to be /C and forward traffic to pool A 

if non of those forward to pool B 

that's Correct ? 

Maybe think about using a local traffic policy rather than an iRule. It will be more efficient and easier for you to manage

Hi Bhupendra , 
As PeteWhite recommended , yes it's eaiser than iRule and will give you the same result. 

it should be like this : 

>>> Note that , the last condition "3rd match " should be All Traffic and then do those Actions ( Log and Forward to default pool ) 

This is an overview about Local Traffic policy : 
https://techdocs.f5.com/kb/en-us/products/big-ip_ltm/manuals/product/local-traffic-policies-getting-started-12-1-0/1.html

Goodluck