A student in Obu'pu Secondary School discovers that he simultaneously needs a pen, an exercise book, an eraser and a ruler, but that he can purchase only one of these items. What is the first thing he is expected to do?
A.
Check how much he has
B.
Find out which is the cheapest of the items
C.
Draw up a scale of preference
D.
Weigh the opportunity cost of each item against the other
