Answer:
The correct answer is, B "changing have to has"
Explanation:
- B: One of tonight's speakers has a long career as a wildlife caretaker, having spent time on three continents observing endangered species in the wild
*using "have" in that situation is grammatically incorrect.
-"Long career", is insinuating the speaker has a past of being a wildlife caretaken, meaning it would be past tense.
Therefore, changing to has, (past tense version of have) would be correct.
Your answer is B.
"How are the other options incorrect:"
-A: One of tonight's speakers have a long career as a wildlife caretaker, have spent time on three continents observing endangered species in the wild
*Its grammatically incorrect.
-C: One of tonight's speaker have a long career as a wildlife caretaker, having spent time on three continents observing endangered species in the wild
*"One of tonight's" Meaning, there is multiple so "speaker" would be plural.
-D: One of tonight's speakers have a long career as a wildlife caretaker, has spent times on three continents observing endangered species in the wild
*This is just grammatically incorrect. There is literally no way this could be the answer.
Hope this helps!
