All of the above.
Assuming that pressure is also kept constant for all five gases, then the answer must be that gas
The identity of the gas can only be determined if information about the mass of the sample is provided in the problem.
Since this is not the case here, you can safely assume that equal numbers of nitrogen gas,
However, they will not have the same mass because these gases have different molar masses.
Since no information about mass was provided, you simply can't say that one of the four options is correct. Using the information given, all four options are correct.