Final answer:
The average mass of tin in this sample is 118.00 amu.
Step-by-step explanation:
The average mass of tin in this sample can be determined from the mass spectrometry data. In the given options, the closest average mass to the atomic mass of tin (118.71 amu) is option A, 219.76 amu. However, this is incorrect because it does not match the actual atomic mass of tin.
The correct average mass of tin in this sample is the same as its atomic mass, which is 118.71 amu. Therefore, the correct answer is option C, 118.00 amu.
It is important to note that the average mass in the mass spectrum is slightly different from the atomic mass due to the presence of different isotopes of tin with varying masses. However, the atomic mass is a weighted average of these isotopes' masses.