Great sums of money have been spent, for example in the...
单项选择题Great sums of money have been spent, for example in the deserts of Egypt, in __________ oil. Sometimes little is found. When we buy a few gallons of petrol for our cars, we pay not only the cost of the petrol, but also part of the cost of the search that is always going on.
A．exporting
B．expecting for
C．prospecting for
