Reversible lanes are marked with unique signs, signals and markings, such as

Reversible lanes are marked with unique signs, signals and markings, such as a red X, which means the lane is closed.
Flashing red X means that you shouldn't drive in that lane, not that you should prepare to stop. A solid yellow X means you should move to another lane, and a flashing yellow X means that you can only use the lane on the left. So this means that a red X is the only correct answer.

Reduction in overall biodiversity