Recently discovered fossil remains strongly suggest that the Australian egg-laying mammals of today are a branch of the main stem of mammalian evolution rather than developing independently from
a common ancestor of mammals more than 220 million years ago.Meaning Analysis:
The sentence is talking about the Australian egg-laying mammals of today. They are a branch of the main stem of mammalian evolution. They did not develop independently from a common ancestor of mammals. Error Analysis:
The sentence is presenting a comparison. It says that Australian egg-laying mammals are X rather than Y.
X = a branch of the main stem of mammalian evolution (a noun phrase)
Y = developing independently from a common ancestor of mammals (a noun phrase that actually starts from an action word – a gerund)
Hence, the entities compared are not parallel. Y also needs to be a noun phrase that starts with a “proper” noun entity.PoE:
A. rather than developing independently from: Incorrect
for the reason stated above.
B. rather than a type that developed independently from: Correct.
“a type…” is parallel to “a branch…”
C. rather than a type whose developments was independent of: Incorrect.
Plural subject “developments” does not agree in number with singular “was”.
D. instead of developing independently from: Incorrect
. Same parallelism error as in choice A.
E. instead of a development that was independent of: Incorrect.
Again, the entities compared are logically not parallel.
So you see, the knowledge of correct usage or “rather than” and “instead of” is not imperative to solve this problem.
Hope this helps.
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