Perseverance is what it takes to achieve one's success. Without perseverance, one may find it hard to realize his dream.
Personally, I prefer quote A, which asks us not to give up but stick with what we're pursuing. Only by trying again and again can we make it at last.
Take Madam Curie for example. To fulfill her academic ambition, she overcame many hardships to go abroad for further education. After her husband's death, she carried on her research work despite a lot of difficulties. Finally, her continuous efforts paid off. She was awarded two Nobel prizes.
So, never give up easily when faced with failure. Hold on to your dream and you'll surely enjoy a sense of achievement.