[单选题]
The binding energy p:z wkv 2ok.4ebpgkx 06e ax i*9vslkry(h2n4l apg88t )r nucleon
A. increases steadily as we go to heavier elements.
B. decreases steadily as we go to heavier elements.
C. is approximately constant throughout the periodic table, except for very light nuclei.
D. has a maximum near iron in the periodic table.