Question

Which agricultural inventions prompted the Sung dynasty’s population growth?

There is more than one answer:
-New methods for breeding livestock were used
-New irrigation techniques were used.
-New strains of rice were grown.
-New strains of wheat were grown.​New methods for breeding livestock were used.
HELP PLEASEEEE

Answer 1

Answer: This made double-cropping possible in some areas, and in some places, even triple-cropping became possible ... the hardiness and productivity of various varieties of rice were and are in large part responsible for the density of population in South, Southeast, and East Asia.

Explanation: Thank you. :)

Answer 2

This made double-cropping possible in some areas, and in some places, even triple-cropping became possible ... the hardiness and productivity of various varieties of rice were and are in large part responsible for the density of population in South, Southeast, and East Asia.