Tori works two jobs to pay for college. She tutors for $30 per hour and also works as a receptionist for $10 per hour. Due to her class and study schedule, Tori is only able to work up to 20 hours per week but must earn at least $200 per week. If t represents the number of hours Tori tutors and r represents the number of hours she works as a receptionist, which system of inequalities represents this scenario?
A t + r greater than or equal to 20
30t + 10r = 200
B t + r less than or equal to 20
30t + 10r less than or equal to 200
C t + r less than or equal to 20
30t + 10r = 200
D t + r less than or equal to 20
30t + 10r greater than or equal to 200