C2RCC clarification

I am using C2RCC for Sentinel 2 data.

Where can i find documentation for the first two options e.g.
Output AC reflectances as rrs instead of rhow? and Derive water reflectance from path radiance and transmittance? ?

I searched relevant documentation reference in the help of C2RCC but i couldn t find in the documents provided where exactly they where discussed.

What is the difference in the output in respect to water surface reflectance ?

Thank you in advance.

Remote Sensing Reflectance, Rrs(λ; sr-1), is water-leaving radiance, Lw(λ), corrected for bidirectional effects of the air-sea interface and sub-surface light field, and normalized by downwelling solar irradiance, Ed(λ), just above the sea surface.