It would be a shallow kind of optimism to assume that the introduction of the art of inventing has been as immediate and unmixed blessing to mankind.
A.It would be a shallow kind of optimism to believe that the introduction of the— art of inventing has directly benefited only mankind. B.It would be a shallow kind of optimism to believe that the introduction — of the art of inventing has benefited mankind directly. C.It would be a shallow kind of optimism to think that the introduction of the art of inventing has blessed mankind immediately and blessed only mankind. D.It would be a shallow kind optimism to believe that the introduction of the art of inventing has benefited mankind directly and brought them only benefit.正确答案D
