Which sentence has a shift in verb tense?

the barrier will drop down every time that a train approaches the crossing.

if anyone knows the answer, she does.

as i came in the front door, eddie is going out the back door.

a row of ants had filed up the chair leg and was about to consume our lunch.

pls

As I came in the front door, Eddie is going out the back door.

Explanation:

b exhibiting favoritism toward the kikuyu people.

genetic variation can be caused by mutation (which can create entirely new alleles in a population), random mating, random fertilization, and recombination between homologous chromosomes during meiosis (which reshuffles alleles within an organism's offspring).