Iq is generally considered the single best index of how well a person will do in school

If this statement answers whether it is true or not, the statement will imply that this statement is true. It is because an IQ is generally considered the single best index of how well a person will do in school, if a person does do well in school, his or her IQ will tell if he or she learns anything or he or she had any knowledge of the teachings that the school has been teaching them.