I did research on this one and the closest ive came to was when i typed sweet in.
"having the pleasant taste characteristic of sugar or honey; not salty, sour, or bitter."a cup of hot sweet tea"<span>antonyms:<span>sour, <span>savory"
so my final answer is A) Antonyms of sweet.</span></span></span>
Answer:
An aspect of the National Geographic video that is unique to video is that viewers can watch the effects of the wind and water as they listen to the narrator.
Hope it helps out !!