Jaya Prithvi Bahadur Singh (23 August 1877 – 15 October 1940), was a humanist, peace advocate, writer and social activist from Nepal. He devoted his life to social welfare and world peace. He is known mainly for humanitarianism, peace advocacy and human rights advocacy for education.
Answer: no body cavity—acoelomates; body cavity not completely lined with mesoderm—pseudocoelomates; body cavity completely lined with mesoderm—coelomates
