Answer: structure B corresponds to the compound 3,4,4-trimethyl-2-pentanone
Step-by-step explanation:
The question requires us to choose the structure that corresponds to the compound 3,4,4-trimethyl-2-pentanone.
The compound 3,4,4-trimethyl-2-pentanone presents a main chain of 5 carbons (indicated by the prefix pent-), with a ketone group bonded to the second carbon in the chain (indicated by the number 2 and the suffix -one). Also, there are 3 methyl groups: the first one is bonded to the third carbon in the main chain, while the other two methyl groups are bonded to the fourth carbon.
We can draw the structure of 3,4,4-trimethyl-2-pentanone as it follows:
(Note that the number of each carbon from the main chain is shown in blue near the C symbol)
Now, let's compare the structure drawn above to the structures provided by the question:
Even though structure A presents a ketone group bonded to the second carbon, the methyl groups are not positioned in the right place. Also, there is only 2 methyl groups bonded to the main chain at the 4th carbon of the chain.
Structure B presents the ketone bonded to the 2nd carbon from the main chain, a methyl group at the 3rd carbon and two methyl groups at the 4th carbon.
Therefore, structure B corresponds to the compound 3,4,4-trimethyl-2-pentanone.