The statements A,C and D are correct.
(A) T is soluble in hot aqueous NaOH. In the alkaline medium, the lactone ring is hydrolyzed to form sodium salt which increases solubility.
(B) U is optically inactive as no chiral center is present.
(C) Molecular formula of W is C10H18O4.
(D) V gives effervescence on treatment with aqueous NaHCO3 as it contains -COOH group which reacts with sodium hydrogen carbonate to release carbon dioxide.