------------ continue to pollute the ocean with all forms of contamination such as plastic containers remains a mystery to environentalists.
a People that
b Why people
c Those people that
d Although people
답은 b인데 이유를 모르겠어요.. a,b,c 다 답이 되지 않나용???

------------ continue to pollute the ocean with all forms of contamination such as plastic containers remains a mystery to environentalists.
a People that
b Why people
c Those people that
d Although people
답은 b인데 이유를 모르겠어요.. a,b,c 다 답이 되지 않나용???

의문사+주어+동사는 3인칭 단수 취급하기때문에 정답은 b
나머지는 주어가 people 임으로 복수동사가 나와야함