Consider a population of 5000 garter snakes. two hundred of those snakes split off from the populationto a new habitat. when the original population dropped from 5000 to 4800, the allele frequencies of variousgenes changed. the evolutionary process that caused the change in allele frequencies in the originalpopulation is: a. a. genetic drift. b.b. mutation. c.c. migration. d.d. stabilizing selection. e.e. disruptive selection.