2.[A] before [B] unless [C] until [D] because
3.[A] interactions [B] assimilation [C] cooperation [D] consultation
4.[A] return [B] reply [C] reference [D] response
5.[A] or [B] but rather [C] but [D] or else
6.[A] considering [B] ignoring [C] highlighting [D] discarding
7.[A] on [B] in [C] for [D] with
8.[A] immune [B] resistant [C] sensitive [D] subject
9.[A] affect [B] reduce [C] check [D] reflect
10.[A] point [B] lead [C] come [D] amount
11.[A] in general [B] on average [C] by contrast [D] at length
12.[A] case [B] short [C] turn [D] essence
13.[A] survived [B] noticed [C] undertaken [D] experienced
14.[A] contrarily [B] consequently [C] similarly [D] simultaneously
15.[A] than [B] that [C] which [D] as
16.[A] system [B] structure [C] concept [D] heritage
17.[A] assessable [B] identifiable [C] negligible [D] incredible
18.[A] expense [B] restriction [C] allocation [D] availability
19.[A] incidence [B] awareness [C] exposure [D] popularity
20.[A] provided [B] since [C] although [D] supposing