![](https://cos-cdn.shuashuati.com/pipixue-wap/2020-1230-1107-53/ti_inject-812ce.png)
the exploration of the botanical world on a large scale.
A.
It was not until the eighteenth and nineteenth centuries that; had begun
B.
It was not until the eighteenth and nineteenth centuries when; began
C.
Not until the eighteenth and nineteenth centuries did; begin
D.
Until the eighteenth and nineteenth centuries; began