Final answer:
The number of apples with defects cannot be determined from the given information.
Step-by-step explanation:
In this scenario, the student is examining a random sample of 150 apples from a truckload to determine the number of apples with bruises and other defects. The first option states that 15 apples are found to have defects, so this is a possible outcome. The second option claims that all 150 apples have defects, which is highly unlikely and unrealistic. The third option states that no apples have defects, which is also highly unlikely. Therefore, the correct answer is that the number of apples with defects cannot be determined from the given information, so option number 4 is the correct choice.