Definition: In this task, you're given a statement and three sentences as choices. Your job is to determine which sentence can be inferred from the statement. Incorrect choices change the meaning in important ways or have details that are not mentioned in the statement. Indicate your answer as 1,2, or 3 corresponding to the choice number of the selected sentence.
Input: Statement: The sensitivity of cost to volume for a postal system can be investigated directly provided the ratio of fixed to variable costs is known by function. Choices:  1. Postal system costs are not linked to volume. 2. Postal system costs are linked to volume. 3. Postal system costs are strongly linked to volume.

2