问题补充：
---is it from your home to the museum? --- About six kilometers.
A. How long
B. How much
C. How far
D. How often
答案：
A. How long
B. How much
(答案→)C. How far
D. How often
解析：How long多长；How much多少元；How far多远；How often多久一次；根据下文，大约六千米。可知前文问的是，从你家到博物馆有多远？故选C。
