If we want to keep up with the high pace of modern life,we had better learn to make the right choice

题目

If we want to keep up with the high pace of modern life,we had better learn to make the right choices about what and how we eat.Because we have so much to choose,many companies offer advice on what we should eat.
答案是在so much to choose 后加from,
我明白加from的意思 ,但我不明白的是这里一定要加from吗?不加的情形不对吗?还有为什么so much 不用改成so many?

答案

这里food是食物的总称,不可数,所以用so much;from是一定要的,因为这里要表达的意思是有很多“可供选择”