问题如下：
which of following can best discribe an invesment holding in 180-day commercial paper?
选项：
A.It is best described as a capital market instruments.
B.It is best described as a money market instruments.
C.It is best described as an intermediate-term debt instruments.
解释：
B is correct.
Money market instruments refer to market securities with maturities of one year or less.
老师，英文不好，commercial paper是什么意思呢？
