The image of the falconer losing control of the falcon in line 2 of “the second coming” probably stands for — a. the tendency of people to rebel against what is good for them b. the difficulty of really mastering any art, such as poetry c. the human desire to be free and wild rather than tame and civilized d. the inability of people to stop civilization’s descent into chaos

The image of the falconer losing control of the falcon in line 2 of “The Second Coming” probably stands for D. the inability of people to stop civilization's descent into chaos.
The falcon is a symbol for civilization, humanity. And given that the falconer lost control of it, stands to symbolize that humanity will also lose control of itself and be lost in the chaos that will indubitably ensue. A trained falcon without its falconer will definitely not have a good life, likewise civilization will lose it all.