A group of students must collect at least $150 to organize a science fair. They have already collected $30. Which graph best represents all remaining amounts of money, in dollars, that the students should still collect to organize the science fair?
A: Number line graph with closed circle on 120 and shading to the right.
B: Number line graph with closed circle on 30 and shading to the right.
C: Number line graph with closed circle on 150 and shading to the right.
D: Number line graph with closed circle on 180 and shading to the right.