22 At the large, unruly gathering, glass bottles and cans were thrown at police officers as they tried to break up the _________.
(A)desert
(B)forest
(C)crowd
(D)building

在這次大型騷亂集會上，當警察試圖驅散_________時，有人向他們投擲玻璃瓶和易拉罐。