Correct Answer: Harsh exclaimed with joy that he was very happy to receive the best student award.

Solution : The second option is the correct choice.

The steps of conversion are as follows:

• The pronoun "I" (first person) is changed to "he" (third person).
• The verb "am" is changed to "was" to match the tense change required in reported speech (the simple present tense is changed to the simple past tense).
• The reporting verb "said" is changed to "exclaimed with joy".
• The connector "that" is used to connect the reporting clause and the reported clause.

Therefore, the correct answer is: "Harsh exclaimed with joy that he was very happy to receive the best student award."