An unmanaged fixed income security portfolio handled by an independent trustee is known as a______________.

Answer: Option C

A unit investment trust (UIT) is a type of investment company that offers a fixed, unmanaged portfolio of securities, typically bonds or other fixed income instruments.

Unlike actively managed funds, a UIT is not actively traded or adjusted by a fund manager after its creation; instead, it is held by an independent trustee who maintains the portfolio until maturity.

This makes UITs distinct because they follow a buy-and-hold strategy, ensuring that the original composition of the portfolio remains largely unchanged over time.

Therefore, an unmanaged fixed income security portfolio handled by an independent trustee is best described as a unit investment trust.