Two students measured the length of the same stick, each using a different 30 cm ruler. One student reported a length of 22 cm, and the other reported a length of 8 cm. The most likely explanation for the difference in the reported values is that one —

A. *student improperly read the ruler

B. ruler was metal and the other ruler was plastic

C. student viewed the ruler from a different angle

D. ruler was constructed with nonstandard cm marks

It is the problem of viewing the scale from different sides or angles. If we assume the actual length of the stick to be 22 cm. Then the first student measured the length by reading the values from 1 cm towards 22 cm on the scale. While, the second student measured the length of the stick by reading the values from the other side or the other angle of the scale, that is, from 30 cm mark towards 1 cm. And in that case the the length of the 22 cm long stick will appear as:

30 cm - 22 cm = 8 cm

Therefore, the second student read 8 cm on scale. So, the correct option is:

C. student viewed the ruler from a different angle