d < 4.5
This means that "d" is a number/value less than 4.5
A. 4.5 This is false because "d" can not be equal to 4.5, it can only be less than 4.5
B. 15 This is false because 15 is greater than 4.5, not less than 4.5
C. -1 This is true because -1 is less than 4.5
Your answer is C
