It's about five walk from my home to my school.

可以说It's "a 5 minute walk".a 5-minute walk（连字符号-英国人可加可不加,不影响理解）
也可以many 5 minute walks.many 5-minute walks
选a)需改为：It's a five minute walk from my home to my school.可行（注意在five minute walk前加了a）
b)minute显然应为复数形式
d）minutes后少了'
类似地还可以说
one-hour sleep
20-minute walk
数-量+名词的这种结构在中文中太常见
我买“两斤肉”.
我今天上了“8节课”.