A pedigree or a pedigree chart is used to track which organisms are carriers of a specific trait through several generations.
C.
If the food is limited to the squirrels then that could impact how well they reproduce which could impact their numbers which therefore could impact the food source for the foxes which eat them. Fewer squirrels means the foxes will slow down on their reproductive numbers as well...they are all linked!
The answer you are looking for is false