# The major product obtained on heating $\gamma$-hydroxy acid $CH_3-CH_2-CHOH-CH_2-CH_2-COOH$ is

$\gamma$-hydroxy and $\delta$-hydroxy acid will give the 5 and 6-membered ring compound (more stable).
$E$-hydroxy and above compounds will give the linear polymeric esters.
Hence (a) is the correct answer.