B protein is the basic substance of cells and the main raw material for the growth and repair of damaged tissues. If the intake of protein is insufficient, it will make people grow slowly, so B is correct;
C, when each gram of oil is completely oxidized in the human body, the energy released is more than twice that of sugar, which is an important energy-supplying substance, so C is correct;
D, human iodine deficiency can cause goiter. Add a proper amount of potassium iodate to salt to supplement the iodine needed by human body, so D is correct.
Because the topic is wrong, the answer is: a.