Mark-net usage

HI, 

I have a large layout and I need to see for example the net name A all the way from M5 to M1. However, when I use connectivity->net->mark the tool highline every thing include any nets which are not connected to net A. 

how can I set the Marknet options form to highline only net A. I want to see if net A connected correctly. 

thanks 

Nhumai