Select the correct Active/Passive form of the given sentence.

“Read the instructions before you start writing your exam,” The invigilator said to the students.

The invigilator told the students to read the instructions before they started writing their exam.

The correct active/passive form of the given sentence is The invigilator told the students to read the instructions before they started writing their exam.

The sentence is in the simple present tense, which is used to describe an action that happens regularly or now. The active voice of the sentence is formed by putting the subject of the sentence before the verb and removing the word "by." In this case, the subject of the sentence is "invigilator" and the verb is "tell." So, the active form of the sentence is "The invigilator told the students to read the instructions before they started writing their exam."

The other options are incorrect because:

• The invigilator told to the students to read the instructions before they started writing their exam.” This is incorrect because the word "to" is used to indicate a command, but the invigilator is telling the students.
• The invigilator told the students to read the instructions before they start writing their exam.” This is incorrect because the word "start" is in the present tense, but the sentence is about an action that is about to happen.
• The invigilator told the students to read the instructions before he start writing his exam.” This is incorrect because the word "he" refers to the invigilator, but the invigilator is telling the students.
• The invigilator told the students to read the instructions before they started writing their exam.” This is the original sentence in the active voice.