(S (S (BASENP (DT The) (NN six) (NN month) (NN study)) (VP (VBD compared) (NP (NP (DT the) (NP (NP (NP (BASENP (JJ environmental) (NN impact)) (COMMA ,) (BASENP (NN health) (NNS risks))) (COMMA ,) (BASENP (JJ economic) (NNS effects))) (CC and) (BASENP (JJ social) (NNS implications)))) (PP (IN of) (NP (BASENP (DT the) (NN use)) (PP (IN of) (NP (NP (BASENP (NN fossil) (NNS fuels)) (COMMA ,) (NP (BASENP (JJ renewable) (NN energy) (NNS sources)) (PP (JJ such) (PP (IN as) (NP (BASENP (NN wind)) (CC and) (BASENP (JJ solar) (NN energy))))))) (CONJP (COMMA ,) (CC and)) (BASENP (JJ nuclear) (NN power))))))))) (PERIOD .))