Which 500mm combo

Hi, which combo do you think makes more sense considering IQ, total price, weight, ... for a 500mm FOV (aprox.)?

A) D700 + 500mm F4
B) D300 + 300mm F2.8
C) D700 + 300mm F2.8 + TC1.7

Thank you

--
A Nikon camera and more lenses than I need, but less than I'd like ...