1 question on linguistics – minimal Pairs

I don’t understand this Linguistics question and need help to study.

1) Which of the following pairs of words would be treated as “minimal pairs”?

car vs. cat

ship vs. strip

tape vs. tap

my vs. climb

pit vs. pat

shoot vs. shaking

bun vs. ban

vote vs. vet

main vs. keep

heat vs. heel

tape vs. tale

bet vs. bell

take vs. tomb

meal vs. heel

vote vs. goat

melt vs. neck

bet vs. vet

fat vs. pat

chain vs. sane