问题补充：
Sweet memories as I looked at the pictures were taken at the beach last summer.
A. took out; which
Bcrowded in; which
C. ended up; that
D. dropped by; that
答案：
A. took out; which
(答案→)B. crowded in; which
C. ended up; that
D. dropped by; that
解析：本题考查动词短语和定语从句。句意：当我看着去年夏天在海滩边拍的照片时，甜蜜的回忆涌上心头。“（想法，问题，往事等）涌上心头，涌入脑海”。sort out“分类”；drop by“顺便拜访”；end up“结束”。
