I think it Should be D because &RC is got global.

But why don't you run it in sas? You will have a definitive answer. Playing with is the best way to learn it.
----- updated: my previous answer is incorrect. According to sas document, macro variables defined outside of any macro are global. So in this case, the value should be assigned by the last time %let statement is used.

Sorry for the wrong answer.

已经上机跑了，答案是low，就是没想明白为什么是这个。

这里有2个变量RC，一个是global, 一个是local.

在macro结束运行的时侯，local 的 RC是low，但是global 的 RC 是Before Execution。题目问的应该是local RC的值。

”Since local symbol tables exist separately from the global symbol table, it is possible to have a local macro variable and a global macro variable that have the same name and different values.”

See my correction above.

local的怎么就是low呢？ totalobs是50 是大于10的，那也应该是运行第一个也就是rc=high啊。
我在想是不是因为是%let 是定义global变量的，所以不受condition的限制。