Question

You'd give an advanced program of studies to students who are interested and able to take it!

1.你应该给那些兴趣广泛又有能力接受(这个高级大纲)的学生制定一个高级大纲。这个解释就是说interested和advanced program of studies 没有关系
2.You'd give an advanced program of studies to students who are interested （by it）and able to take it! 这就强调interested和大纲有关系的，是省略了by it，就是说被大纲吸引(即对其有兴趣)

您同意那种啊？

Answer 1

第二种。

interested的用法:
be interested in sth.对。。。有兴趣 （注意这里是in sth.你说的by 是错的）
这种理解的话这里省略了in it.

另外还有有兴趣做某事:be interested to do sth.
这里你也可以这样理解，who are [interested and able] to take it.
interested 和able结构上并列。
完整的形式:who are interested to take it and able to take it.

Answer 2

第二种