The old couple don't want to _______ their son and still live in the countryside although their son urged them to move to the city and live with his family several times.
The way ______ was thought of by him ______ the experiment was similar to the way _____ you carried it out.
A. that, doing, which B. which, of doing, in which
C. what, to do, \ D. it, of doing, that