People have been manipulating (操纵) organisms for human benefit since at least the dawn of agriculture, genetic editing is becoming widespread, and a few artificial organisms have been manually assembled in the past few years — copying the body forms of known animals. But this research, for the first time ever, “designs completely biological machines from the ground up, “the team writes in their new study.

What does the underlined sentence probably mean?

A．People never created these biological robots in history.

B．These machines were copied from the very beginning.

C．The research is completely carried out on the playground.

D．Organisms have been developed since agriculture.