Hi MI.. :)
46) If β>α then, Total units of X available in the economy is greater than total availability of Y.
Now, both agents have "min" utility function..So, both would like to consume equal amount of x and y.
As total X > total Y ..so, some units of x remain undemanded.
It means market for x will not clear for any positive price.
So, it must be the case that "x" needs to be freely available so that its market can be cleared.
Hence, option(c): If β>α then , px=0.
For more clarity, You can assume certain value of α and β , draw edgeworth, IC's and check yourself.. :)
:)