One mole of a symmetrical alkene on ozonolysis gives two moles of an aldehyde having a molecular mass of 44 u. The alkene is

When a symmetrical alkene is subjected to ozonolysis, it yields two moles of an aldehyde with a 44 g/mol molecular mass. 2-Butene is the alkene. On ozonolysis, 2-Butene in both its cis and trans forms yields 2 moles of 44 g/mol acetaldehyde. Ozone breaks the double bond in alkenes in this ozonolysis reaction, forming two carbonyl groups.

Hence, the correct answer (A) 2-Butene.