Pluto was ruled not a planet anymore because it is a "dwarf planet"
Apparently, the International Astronomical Union's (IAU) definition of a planet includes that a planet should be part of a body that would orbit the sun.
According to the IAU, there are three criteria's that contribute to a planet being called a planet.
1. It is within orbit around the Sun.
2. It has a sufficient mass to assume a nearly round shape
and 3. It has "cleared the neighborhood" around it's orbit.
Pluto only so happens to meet 2 of these requirements, not including the third option.
The structure for this question is attached. I think the correct answer would be the fourth option. The common name of the structure would be ethyl isobutyl ketone. Other name would be 2-methyl-3-pentanone. It has a chemical formula of C7H14O or (CH3)2CHCH2C(O)CH2CH3. It is classified as an aliphatic ketone and is used as a solvent and a reagent in laboratory experiments. It is a VOC or volatile organic compound. This compound can also be found at times in normal human biofluids and in feces for about 25% of the population. At normal conditions, it exists as a solid compound.