Sentence Correction

Before its independence in 1947, Britain ruled India as a colony and they would relinquish power only after a long struggle by the native people.
Before its independence in 1947, Britain ruled India as a colony and they would relinquish power
Before independence in 1947, Britain had ruled India as a colony and relinquished power
Before its independence in 1947, India was ruled by Britain as a colony and they relinquished power
Before independence in 1947, India had been ruled as a colony by Britain, which relinquished power
Before independence in 1947, India had been a colony of the British, who relinquished power

first 2/3 split b/w its independence and independence
there is NO proper anticedent for its so left with option B,D and E
second split
in B improper comparision b/w participle and simple past
third split B/w D and E

I googled and found OE by Ron saying "ruled as a colony" is unclear.
https://www.manhattangmat.com/forums/bri ... t2008.html

OA says E , my query , how "who" can used for "British" representing a country though it should be used for person