【求助】GWD13 Q32 -- Macrophages in Mice 答案后半部分不懂

JNC913

Macrophages are cells that play a role in the response of the immune system of mice and other mammals to invasive organisms such as bacteria.  Unlike other mice, mice that are genetically incapable of making these particular cells do not show elevated levels of nitrates when infected with bacteria.
The statements above, if true, provide the most support for which of the following conclusions?
A. Mice that are unable either to make macrophages or to make them in sufficient numbers will protect themselves from bacterial infections in some other way
B. Mice that show elevated levels of nitrates can easily fight off most types of bacterial infections.
C. In mice, macrophages play a role in the production of nitrates or inhibit a process by which nitrates are broken down or otherwise eliminated.
D. When a healthy mouse becomes infected with an invasive organism, the number of macrophages in the mouse’s body decreases.
E. Injections of nitrates into mice that lack macrophages will not enhance the ability of these animals’ immune systems to fight off infection.

C 中的后半句怎么理解？文中只是说没有elevated levels，也推不出原来nitrates会break down 或者减少啊？

JNC913

所以inhibit的mechanics是通过produce nitrogen， right？ 我想我明白了，谢谢！

sdcar2010

inhibit a process --> block that process --> nitrate INCREASES!  Because that particular process CONSUMES nitrate.  No process? No consumption of nitrate!