ELSS (Equity Linked Savings Scheme) qualifies under Section 80C, has a 3-year lock-in, and invests primarily in equity. It can deliver higher long-term returns with higher volatility.
PPF is a government-backed fixed-income product with an 15-year horizon (extendable), EEE tax treatment, and very low risk. Returns are notified by the government and are modest compared with equity over long periods.
NPS has its own tax benefits (including an extra deduction under 80CCD(1B) in many cases), a mix of equity and debt options, and is primarily a retirement vehicle with restrictions on withdrawal.
There is no single winner. Many households use a combination: some ELSS for equity + tax saving, PPF for safety, and NPS for retirement discipline. Suitability depends on your age, existing 80C utilisation, and risk capacity.