Groher faucet and pop-up drain assembly

What do I use to install (seat?)the drain assembly in the sink--plumbers putty or Hercules Plumbers Caulk?
Thanks very much in advance.
Alan

Putty!!!!!!!!!!!!

One more question--I hope!

The Grohe faucet had two supply lines about sixteen inches long,and sure enough,too short.
I do not want to take the faucet apart.
Is there a riser sold that I can attach to the stops to get a couple of inches more?
If a risers is not an option,can I link another four inch supply line to the current lines?
Thanks.
Alan

Lav supply extensions

3/8" OD copper tube with 3/8" compression union

3/8" x 1/2" lav supply with 1/2" mip x 3/8" compression fitting