What does the text say about the 'Unmanifest' or 'causal body' and how can it be transcended?

According to the teachings in Chapter 50, the 'Unmanifest' (Avyakruta) is also known as the 'causal' (karana) body of the soul. It is described as being with the reflection of consciousness and the cause of pure ignorance. The text states that the ignorance of the Soul is the cause of this body. The only way to achieve the removal of this causal body is through the knowledge of the unity of Brahman and the Soul. This process of removing ignorance is what leads to liberation, or Moksha, which is defined as abiding in one's own form.