If a Prairie Dog Had the Opportunity to Perform an Altruistic

If a prairie dog had the opportunity to perform an altruistic act (that is, give an alarm call) to help its relatives, which combination of the following relatives would the prairie dog be most likely to help (base your answer solely on the genetic relationships) ?

A) two nieces, two cousins, and one half-brother
B) two half-sisters and two nieces
C) one son, one niece, and one half-sister
D) equal altruism to all combinations described