请问just as...so结构，一道题目

E10—5 Just as reading Samuel Pepys’s diary gives a student a sense of the seventeenth
century of its texture and psyche-so Jane Freed’s guileless child narrator takes the operagoer inside
turn-of-the-century Vienna．
(A)so Jane Freed’s guileless child narrator takes the operagoer
(B)so listening to Jane Freed’s guileless child narrator takes the operagoer
(C)so the guileless child narrator of Jane Freed takes the operagoer
(D)listening to Jane Freed’s guileless child narrator takes the operagoer
(E)Jane Freed’s guileless child narrator takes the operagoer to her opera

答案是B，很标准的just as...so结构。有一个迷惑选项是D，跟B的差别，除了so，其他都一样。

但是似乎刘继民的书里面，也有很多不带so的，比如

E10—4 Even as they never forgave the Crusaders who overran their homeland，the Syrians
have never absolved the French for taking territory from them．
(A) Even as they never forgave
(B)While they never forgave
(C)Just like they never forgave
(D)Similarly to not forgiving
(E) In spite of their never forgiving

请问，这个结构中，"so"是必须的吗？

固定结构 Just as A do，so B do

我上新东方的时候老师说的