A. balance :A. upset = A. serious = A. promote = A. aware = A. solution = A.combine = A. disappear : A. awareness 0: A. environment 1: A. natural B. issue B. tortoise B. influence B. support B. protect B. habitat B. harmful B. average B. illegal B. electrical B. chemical C. panda C. wildlife C. energy C. research C. impact C. C. disease endangered C. consequence C. importance C. ecosystem C. atmosphere D. extreme D. heatwave D. pollutant D. nature D. danger D. awareness D. destroy D. negative D. atmosphere D. material D. solution