Hi Safian Kishna ,
For me ur input is not clear ...
.
The signature may have significance with the logic used to write the program .Unless until it have document .I will be hard to decode it..
But I can answer ur question by explaning Factory Pattern ..
See we can use the to get an instance of MaleFP class , In more generic term to get instance of PersonFP class .
This is possible because of inheritance .
According to the logic of this program ...
when this line get executed
-Itz constructor get callled
As a result it will displace then supplied..
I hope this helps u.