Which of these options is a compound-complex sentence?

Choose 1

(Choice A)
A
In the early 20th century, a Louisiana congressman named Robert Broussard proposed a dangerous, innovative plan to fight an invasive plant species: he intended to introduce and farm hippos for meat in the Mississippi River.

(Choice B)
B
In the early 20th century, a Louisiana congressman named Robert Broussard proposed a plan to fight an invasive plant species: he intended to introduce and farm hippos for meat in the Mississippi River, even though hippos are extremely dangerous animals.