Nick works two jobs to pay for college. He tutors for $15 per hour and also works as a bag boy for $8 per hour. Due to his class and study schedule, Nick is only able to work up to 20 hours per week but must earn at least $150 per week. If t represents the number of hours Nick tutors and b represents the number of hours he works as a bag boy, which system of inequalities represents this scenario? (1 point)

Select one:
a. t + b greater than or equal to 20
15t + 8b = 150
b. t + b less than or equal to 20
15t + 8b greater than or equal to 150
c. t + b less than or equal to 20
15t + 8b less than or equal to 150
d. None of the systems shown represent this scenario.