Unsupported. All higher primates are thought to have evolved from a single diurnal species of lower primate. Some lemurs are the only living diurnal lower primates.

Chimpanzees might have evolved from a diurnal lower primate that’s now extinct.

Very strongly supported. As shown below, “lower primate” is a necessary condition of “indigenous Madagascar primate.” Taking the contrapositive tells us that if a primate is not a lower primate (i.e. if it’s a higher primate), then it is not indigenous to Madagascar.

Unsupported. Just because all higher primates are thought to have evolved from a diurnal lower primate does not necessarily mean that all higher primates are diurnal. Some might have evolved to become nocturnal.

Unsupported. If something has opposable thumbs, then it’s a primate. But being a primate isn’t sufficient to establish whether something has opposable thumbs. Lemurs are primates, but we don’t know whether they have opposable thumbs or not.

Unsupported. We don’t know that all lemurs are diurnal. Some lemurs are the only living diurnal lower primates, but there might still be some lemurs that are nocturnal.