Which of the following is not a poisonous indoor plant?

The spider plant is known for being non-toxic and is considered safe for indoor environments, making it a popular choice for households, especially those with pets or young children. This particular plant is appreciated not only for its attractive appearance but also for its ease of care and ability to improve indoor air quality.

In contrast, the other plants listed, such as philodendron, pothos, and oleander, contain compounds that can be harmful if ingested. Philodendron and pothos belong to the same family and contain calcium oxalate crystals, which can cause irritation to the mouth and throat if consumed. Oleander is particularly dangerous, as all parts of the plant are toxic and can lead to severe health issues if ingested. This makes the spider plant distinct from the other options regarding safety and non-toxicity in indoor settings.