Step 1: Legal Principle
A company is an artificial legal person, and its nationality is usually determined by the location of its registered office.
Step 2: Evaluate options
- Residence of shareholders: Not a legal basis for company nationality.
- Place where books are kept: Related to accounting, not nationality.
- Registered office: Legally recognized address of the company—used for jurisdiction and legal identification.
Hence, the correct answer is Option B.