Read the passage and then answer the question: In the early days of automobiles, rain was a real problem for drivers. Water covered the windshields, so drivers had to open their windows and stick their heads outside to see! When Mary Anderson saw drivers struggling in the rain, she thought she could help. Anderson started working on designs for a rain-clearing device. Even after many failures, she kept experimenting. This **persistence** resulted in Mary Anderson's invention of the modern windshield wiper. Her design put a rubber blade on a wooden stick. Today's wipers use the same basic principle that Mary Anderson dreamed up in 1903. What is the meaning of "persistence" as used in the passage? * 1.the quality of continuing in spite of difficulty
2.the lack of a sense of humor
3.a feeling of confusion or bewilderment
4.a feeling of sorrow or great sadness