Which of the Following Is an Example of a Trade-Off

Which of the following is an example of a trade-off imposed on an organism that reflects an evolutionary compromise in function?

A) Patients who became infected by a novel flu strain had had no previous exposure to that particular strain.
B) Sturdier bones would prevent fractures but would also reduce an organism's mobility.
C) The crossing of air and food pathways in humans increases the risk of choking.
D) Recent changes in human diet contribute to metabolic diseases.