ParthSanghavi hey there !
Lemme try :
The members of the scavenger team were discouraged when they realized the ocean in [their sector was so deep as to be bottomless, so they decided immediately to terminate] their search and assist other teams.
Meaning:
Members of X were discouraged..why?? Because they realised that the ocean in their sector was deep... The extent of the deepness was so much that it FELT as if it were bottomless ( not actually bottomless...an ocean cannot be bottomless..that is much general knowledge)...so they quit Thier project and decided to....
The key point here is understanding that the members FELT as if it were bottomless...it is more of a metaphorical way of speaking to emphasize the emotion..just as we say "sky is the limit" is it actually the limit?? Nope...but yet we say it to emphasize the emotion..
Errors analysis:
Members(plural...were(plural)...they...their - all SV pairs are accounted for ...no pronoun problem.
Verb tense is also correct as all the things actually happened at almost the same time.
Modifier - there is no modifier
Parallelism: all verbs are parallel ...
Idiom : so X as to Y
Here X is the cause
Y is the effect...
Ocean was so deep(X) as to be bottomless (Y) ... The ocean was so deep that the effect felt like the ocean was bottomless...
So answer choice A is correct
b. their sector was so deep it could have been bottomless, so they decided to immediately terminate
- here we are actually trying to say that the ocean actually is bottomless... How can that be?? 5th standard science : earth is made up of matter and the water surface is on that matter so there actually is a bottom ... In option A the idiom " so X as to be Y" does not actually convey LITERAL meaning , it is more of a metaphorical... But in option B ,directly stating "it could have been bottomless" is straight-away wrong...
With the same analysis you can eliminate C and D
Option E does convey the intended meaning BUT the idiom " enough to be" actually Coveys a meaning that the sector of ocean is sufficient to be called as if there is a measure of deepness of ocean to be called bottomless..like it could be even more bottomless but right now the depth is enough to be called bottomless... whenever you see "enough" , always try to ask that is that the intention of the noun?? Or the verb?? As in is the author trying to prove a sufficiency or does he want to emphasize an emotional response...
Where is enough right :
There was enough charge in the batteries to give me a headstart.. here the charge is actually playing a role in a way by giving me a headstart...it means that this much charge is sufficient for me to get a headstart...there could be more charge but right now this much is enough
Take away :
So X as to Y : X is cause..Y is effect
Enough to : sufficiency ( always be careful about this idiom ..unless and until we are talking about sufficiency the use of this idiom may not be best )
Try to use general knowledge and then assimilate it with the intended meaning...I guess you didn't look for the meaning part...
Hope this helps
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