Directions: Fill in the blanks with the best option to make it a correct sentence.

The remarkable fact that many inventions had their birth as toys suggests that people philosophize more freely when they know that their _________ leads to no _________ results.

To fit the idea of inventions originating as toys, we want the second blank to suggest “results” that are not serious or important - the opposite of what we’ll think about toys. Hence, “weighty” (of great significance or moment; serious) fits our prediction for second blank. Moreover, “speculation” (consideration, thinking) gives a coherent meaning to the sentence. Hence, (5) is the answer.