How to select region in imported orphan mesh

Hi

 

I am new to Abaqus and trying to model breast deformation using the CEA.

I have imported the patient's geometry as an orphan mesh ( part has three sets each corresponding to fibroglandular tissue, fatty tissue, and implanted clips).

I want to select the region of breast close to chest-wall and assign zero displacement boundary condition.

My question is how do I select all the nodes/faces in the desired region of the part?

thanks

Prab