linux - How to replace a list of strings by another list

I have a file which has (many) strings I'd like to replace, so I thought about using a simple command like:

sed 's/string1/string2/g' file1 > out  

However, there are too many strings for that to be repeated manually. So I made a list of all the strings to be replaced, each in a line, and named it file A. Then I made a list of all the replacement strings, and named it file B.

Is there a way to do something like:

sed 's/line i of file A/line i of file B/g' file1 > out

for each line of file A?