The input impedance $\left(\text{Z}_i\right)$ and the output impedance $\left(\text{Z}_o\right)$ of an ideal transconductance (voltage controlled current source) amplifier are
- $\text{Z}_i=0, \text{Z}_o=0$
- $\text{Z}_i=0, \text{Z}_o=\infty$
- $\text{Z}_i=\infty, \text{Z}_o=0$
- $\text{Z}_i=\infty, \text{Z}_o=\infty$