英语高手请进 说明为什么

英语高手请进 说明为什么
1.I___an article about a doctor called Lin Qiaozhi,a specialist in women's diseases.b
A.came on B.came across C.came up D.came out
2.Over the past half century,using chemical fertilizers___very common in farming.a
A.has become B.have become C.had become D.would become
3.With all these attractions,no wonder tourism is increasing___there is in Disneyland.c
A.whichever B.whenever C.wherever D.whatever
4.I don't know what happened in my school during my holiday in Britain and___.a
A.nor do I care B.I don;t care,too
C.nor I care D.nor I do care
重点说明第四个