Explanation

The question stem here gives some shreds of information, but it is not generous. When we compare, say, the cost of 4,801 units and that of 4,800 units, we don't know whether we are going up by a dollar or a factor of ten. Anyway, on to the data statements. Statement (1) tells us the cost of 4,600 units. 4,800 units is a greater number of units, so it will cost more, but we don't know how much more. So Statement (1) tells us that the cost of 4,800 units will be more than $30,000; that means it could be below $40,000 or above $40,000. So Statement (1) is insufficient. Statement (2), on the other hand, is a little different. We know from this statement, by the same logic, that the cost of 4,800 units will be greater than $50,000. That means, in any case, it will be greater than $40,000, as the question is asking. Therefore Statement (2) is sufficient.

The correct answer is (B).