[Grammar] Reserved seats/ seat/ seating for the concert is available at the box office...

[wotcha]

"Reserved seats/ seat/ seating for the concert is available at the box office for an additional fee"


The answer for the above sentence is 'seating'.

I wonder why we can't say reserved seat(s).

:?:

 

[Rover_KE]

'Reserved seats' would need to be followed by 'are available'.

'Reserved seat...is available' is unnatural.