Which of the following terms refers to the remaining gain by producers after accounting for respiratory losses?

The term that specifically refers to the remaining gain by producers after accounting for respiratory losses is net primary productivity. This concept encompasses the amount of organic matter or biomass that is available for consumption by herbivores and ultimately for higher trophic levels in an ecosystem.

Gross primary productivity captures the total amount of energy captured by photosynthesis, but it does not account for the energy lost to respiration by the producers themselves. Therefore, to obtain net primary productivity, one must subtract the energy used for respiration from the gross primary productivity. This results in a measure that reflects the energy available to support growth and reproduction in plants, making it a critical factor in understanding ecosystem productivity.

Other terms such as net energy yield and net biomass gain may imply some measurement involving energy or biomass, but they do not specifically distinguish the producer's gains after respiration, which is precisely what net primary productivity signifies in the context of ecological energy flow.