The correct answer is D. kokari. The correct translation of the sentence "The students are hardworking" in Hausa is "Daliban na da kokari". Here, "daliban" means "students", "na da" is a verb phrase that means "are" or "have", and "kokari" means "hard work" or "hardworking". So, the correct answer is D. kokari. Note: "Kokari" is a noun that means "hard work" or "effort", and it is often used to describe someone who is hardworking or diligent