Two students did a set of experiments on ketones X and Y independently and obtained the following results.

The ketones X and Y are respectively

A

2-ethylcyclobutanone and 3-ethylcyclobutanone

B

2-methylcyclopentanone and 3-methylcyclopentanone

C

3-methylcyclopentanone and 2-methylcyclopentanone

D

3-methyl-4-penten-2-one and 4-methyl-1-penten-3-one