Logical Deduction

1. 
   The clues "The Doctor is the grandfather of F" and "B is the mother of F and E" immediately establish a three-generation family. B is the mother in the middle generation, and the Doctor is the grandfather in the top generation.
   


2. 
   We are given two married couples: (1) Manager D is married to A, and (2) Jeweller C is married to the Advocate.
   


3. 
   Since B is the mother, she must be part of a married couple. From the pairs above, she must be the Advocate, which means her husband is C, the Jeweller. This pair makes up the parent generation.
   


4. 
   The other married couple, D (Manager) and A, must therefore be the grandparents.
   


5. 
   We know the grandfather's profession is Doctor. Since D's profession is Manager, it logically follows that A must be the Doctor and, therefore, the grandfather of F and E.
   

Final Family Structure

Grandparents: A (Doctor) & D (Manager)
      |
Parents:      C (Jeweller) & B (Advocate)
      |
Children:     F (Psychologist) & E (Engineer)

Conclusion:Profession of A is Doctor

Final Answer: The correct option is D