sat suite question viewer
The relationship between genomes and epigenomes reveals how cells with identical DNA develop different blank whereas the genome in each cell contains a complete DNA sequence, the epigenome consists of chemical compounds that determine which traits in the sequence will be expressed.
Which choice completes the text so that it conforms to the conventions of Standard English?
Explanation
Choice D is the best answer. The convention being tested is the use of a colon within a sentence. In this choice, the colon correctly introduces the following explanation of the different functions of genomes and epigenomes.
Choice A is incorrect because it results in a run-on sentence. The two main clauses ("The relationship…functions" and "whereas…expressed") are fused without punctuation and/or a conjunction. Choice B is incorrect because it results in a comma splice. A comma can’t be used in this way to join two main clauses ("The relationship…functions" and "whereas…expressed"). Choice C is incorrect. Without a comma preceding it, the conjunction "and" can’t be used in this way to join two main clauses. Furthermore, "and" fails to indicate that what follows is an explanation of how cells with identical DNA develop different functions.