Step 1: Understanding the Concept
Check the monomers and linkages of each polymer to see which contains nitrogen.
Step 2: Check each option
Bakelite is made from phenol and formaldehyde, so there is no nitrogen.
Dacron is a polyester of terephthalic acid and ethylene glycol.
Rubber is a polymer of isoprene.
Nylon-6,6 is made from hexamethylenediamine and adipic acid and contains amide links \(-\text{CONH}-\).
Step 3: Compare the options
Only nylon-6,6 contains nitrogen.
Final Answer:
Nylon-6,6 is the polymer containing nitrogen.
\[ \boxed{\text{(D) }\text{Nylon-6,6}} \]