The correct answer is A. Provident fund.
A provident fund is a savings account that is used to provide for retirement or other financial needs. It is a form of social security that is funded by both employees and employers. The money in a provident fund is invested in a variety of assets, including stocks, bonds, and real estate.
A life insurance certificate is a contract between an insurance company and an individual. The insurance company agrees to pay a death benefit to the beneficiary of the policy if the insured person dies. The amount of the death benefit is usually based on the amount of premiums that have been paid into the policy.
A national savings certificate is a type of government bond that is issued by the central bank of a country. National savings certificates are typically offered at a lower interest rate than other types of government bonds, but they are also considered to be a safer investment.
Long-term government bonds are a type of debt instrument that is issued by the government. Long-term bonds have a maturity of more than 10 years, and they are typically used to finance large projects, such as infrastructure or defense.
Of the above options, only provident fund is not a national debt.