Named reactions

The structure of the carbonyl compound P is

The structure of product L is

In the following reaction sequence, the correct structures of E, F and G are

$$\ce{PhCO-^{13}CH2-COOH}\xrightarrow{\text{Heat}}[\mathbf E]\xrightarrow[\text{NaOH}]{\ce{I2}}[\mathbf F]+[\mathbf G]$$

(* implies ¹³C labelled carbon)

The structures of compounds J, K and L, respectively, are

Which one of the following reagents is used in the above reaction?