If you own an office building debt-free, it is 100% occupied, and the sole tenant is the U.S. federal government with 10 years remaining on their lease, you could rightfully regard the investment at the point of acquisition as:
Owning a 10-Year U.S. Treasury Bond that carries typical real estate risks inclusive of an illiquidity risk premium
Owning a 10-Year U.S. Treasury Bond that carries only an illiquidity risk premium
The same as any other real estate investment, regardless of the nature of the tenant
Nothing like a 10-Year U.S. Treasury Bond
Exactly the same as owning a 10-Year U.S. Treasury Bond