Answer:
C. Charlie is exactly six years old today.
Step-by-step explanation:
Time can be measured in two ways, absolute time and relative time. Absolute time is the absolute quantification of time in observer's own frame of reference. Relative time is measured when the frame of reference is not set and time is compared between two frames. Here, only option c measures time absolutely as six years old. Rest options compare time between two systems. For example, in option A. Devin's absolute age is not given but a comparison is done between her and Paulo's age. Hence, option c is correct.