How is $()t$ interpreted as it is used in the inflation premium formula?

$()t$ is the value of the Fisher effect.

$()t$ is the rate of change in the consumer price index.

$()t$ is the value of the inflation adjustment included in a nominal interest rate.

$()t$ is the consumer price index value at time $t.$

The term structure of interest rates compares similar bonds based on which variable?

Time to maturity

Taxability provision

Level of default risk

Degree of liquidity