Observations versus Model-Based Statements about the Sun

[lbtocth]

A solar model is used to calculate the expected temperature and density at all depths within the Sun. These results are then used to calculate the expected fusion rate within the Sun. We have confidence that the model is correct because it agrees with the observed characteristics of the Sun. Which of the following observations can be used to check that we really do know the Sun’s internal fusion rate?
Select all that apply.

-Measurements of the Sun’s total energy output into space
-Measurement of the Sun’s mass
-Observations of neutrinos coming from the Sun
-Observations of the total X-ray emission from the Sun’s corona
-Measurements of the varying number of sunspots on the Sun over time

Note: I keep getting the wrong answer. I need help.

 

[mfb]

The total energy output matches the energy released in fusion reactions, so that's working for sure.
We also know the relative importance of fusion reactions, so measuring the neutrinos we can calculate the fusion rate.

The Sun's mass doesn't tell us the fusion rate (or just indirectly via the model that we want to test), and other surface/corona effects are not linked to the fusion rate.

 

[Delta2]

The Sun's mass doesn't tell us the fusion rate

Well I am no good in fusion/fission but aren't the nuclear reactions of Sun converting mass to energy so if we know the rate of decrease of mass, we know the rate of energy radiated?

 

[mfb]

You would have to subtract the mass loss from solar wind, and it's a difficult measurement - in principle yes, but that's not what the question is about.