To uphold and protect the sovereignty, unity and integrity of India is a/the:

Correct option is B

The correct answer is (b) fundamental duty.

• The fundamental duties of the Indian Constitution are listed in Article 51A of Part IV A of the Constitution.
• The duties were added to the Constitution in 1976 by the 42nd Amendment and an additional duty was added in 2002 by the 86th Amendment.
  

Information Booster:

• Fundamental rights are the basic human rights enshrined in the Constitution of India which are guaranteed to all citizens.
• They are applied without discrimination on the basis of race, religion, gender, etc. Significantly, fundamental rights are enforceable by the courts, subject to certain conditions.
  

A legal right is a right that is recognized and enforceable by law. If a legal right is breached, a person can go to court to enforce it. Some examples of legal rights include:

• Freedom of speech
• The right to speak, write, and share ideas and opinions without government punishment.
• Civil rights
• Guarantees of equal social opportunities and protection under the law.
• Right to a fair trial 
• Right in  ownership of property, such as land or a car, where the right is enforceable against the world at large.