The correct transformation of the given sentence into Indirect Speech is:

"The teacher advised him to do his work with dedication."

Here's why:

• Indirect Speech: We need to change the reporting verb ("said") and the pronouns ("teacher" and "you") to reflect the new grammatical structure.
• Advice: "Advised" is a suitable reporting verb for conveying the teacher's instruction and recommendation regarding dedicated work.
• Subject pronoun: Since the direct speech uses "your" work, we change it to "my" work in Indirect Speech to maintain clarity and consistency with the speaker ("me").