Lactic acid on heating with conc. $H_2SO_4$ gives

For which of the following reactions is the anti-Markovnikov addition most suitable?

Oxymercuration-demercuration of allylbenzene $(C_6H_5CH_2CH=CH_2)$ produces:

The major product of the following reaction is:

The product $(A)$ of the given oxymercuration-demercuration reaction is:

In polyenes that contain differently substituted $(C=C)$ double bonds,it is possible to hydrogenate chemoselectively one $(C=C)$ double bond. The product of the reaction of limonene with one mole of $H_2$ in the presence of $PtO_2$ is: