The higher the ratio of oxygen-18 to oxygen-16 in the shells of organisms that lived in the sea during the geologic past, the the climate at that time.

i believe it would cause an increase of percipitation, though i could be wrong. so i would say b is the answer.

answer: national resource conservation services

national resource conservation services is the us. based approach that provides technical and financial assistance for natural resource management. nrcs society in conservation of resources by involving in activities like farmland protection, flood prevention, watershed protection, urban conservation, conserves economic and environmental conditions. it conducts soil surveys and implements the policy of natural resources management on the society.