In my opinion A is correct as others have rightly pointed out the mistakes in other 4 options
Reg Option A structure
[Scientists at oxford] Subject
Have recently found[verb]
That[subordinate clause] animals across the evolutionary spectrum have a keen sense of quantity.
This is whole sentence on its own.
The next portion after the comma is a modifier that modifies this previous clause.
Within the modifier question is testing us on the usage of idiom “not just” X but “y”
Hope it helps.Kudos if it was
...
Reg Option A structure
[Scientists at oxford] Subject
Have recently found[verb]
That[subordinate clause] animals across the evolutionary spectrum have a keen sense of quantity.
This is whole sentence on its own.
The next portion after the comma is a modifier that modifies this previous clause.
Within the modifier question is testing us on the usage of idiom “not just” X but “y”
Hope it helps.Kudos if it was
...






