According to the International Union of Pure and Applied Chemistry (IUPAC), IUPAC nomenclature of organic chemistry is defined as the system of naming organic chemical compounds.
There are certain rules for naming organic chemical compounds as per IUPAC. The name of given (CH3)2CHCH2CH=CH2 will be based on the same rules.
At first find out the longest continuous chain and number the chain consecutively (preference given to double and single bonds), so numbering will start from right to left. the given chemical is 5 Carbon chain long.
Then, identify the groups attached to this chain. Methyl is the only group attached to this chain at 4 Carbon.
Assemble the name in alphabetical order using the full name using correct prefix and suffix.
4-Methyl-1-pentene is the name of this chemical, as methyl is in 4th carbon position, Pent for 5 carbon chain and -ene (suffix) for one double bond).
Hence, the correct answer is "4-Methyl-1-pentene".
