Question

Which type of transistor biasing compensates for the variation in temperature in transistor?

Answer 1

It says that by connecting a diode between emiter and ground like on the schematic, that is theoretically "the same" as the one that exists between base and emiter, we compensate for current variations on the output due to Vbe changing aprox. -2mV/°C in a PN junction as both the diode and the pn junction in the transistor vary in the same way compensating each other.

On the schematic we assume the transistor is correctly biased.