When Babbage was working atprefix = st1 /Cambridge, a new idea occurred to him. He wanted to construct a calculating machine to work out the solutions to maths problems not only with correctness but also with a speed beyond the power of any human mind. His machine could solve problems involving long rows of figures in one continuous operation .        In 1822 Babbage exhibited his invention and won a prize from the government. After that, he immediately started to work on a larger machine designed to solve more difficult problems. Although he received some money left by his father, the money was not enough to support his design. He wrote to the government about his plan and was givenPS2500 to start with, a sum worth much more in those days than it is now.        Babbage continued his work inLondonfor four years. Then his health broke down, and he had to take a long holiday abroad. When he returned toLondonin 1828, he was at the end of his resources. Many bills remained unpaid. His chief assistant and co-workers quarreled with him and left with many expensive tools. For one year no work was done. During this period, Babbage, whose mind was always active, suddenly thought of a completely new idea for the machine. He rushed to meet the government officials to explain his new idea. But this time, they were unwilling to help him. For eight years, they refused to say whether they wanted the machine or not, and their final answer was "No."        From 1828 to 1839, Babbage held the position of professor atCambridgevery successfully. But his greatest work was the unfinished calculating machine which stood covered in dust in his house. It was the beginning of the modern computer. Babbage failed to continue his research work in 1828 mainly because   _  .
he was in poor health he almost ran out of money his co-workers argued with him he spent all his money on his bills
Question: When Babbage was working atprefix = st1 /Cambridge, a new idea occurred to him. He wanted to construct a calculating machine to work out the solutions to maths problems not only with correctness but also with a speed beyond the power of any human mind. His machine could solve problems involving long rows of figures in one continuous operation .        In 1822 Babbage exhibited his invention and won a prize from the government. After that, he immediately started to work on a larger machine designed to solve more difficult problems. Although he received some money left by his father, the money was not enough to support his design. He wrote to the government about his plan and was givenPS2500 to start with, a sum worth much more in those days than it is now.        Babbage continued his work inLondonfor four years. Then his health broke down, and he had to take a long holiday abroad. When he returned toLondonin 1828, he was at the end of his resources. Many bills remained unpaid. His chief assistant and co-workers quarreled with him and left with many expensive tools. For one year no work was done. During this period, Babbage, whose mind was always active, suddenly thought of a completely new idea for the machine. He rushed to meet the government officials to explain his new idea. But this time, they were unwilling to help him. For eight years, they refused to say whether they wanted the machine or not, and their final answer was "No."        From 1828 to 1839, Babbage held the position of professor atCambridgevery successfully. But his greatest work was the unfinished calculating machine which stood covered in dust in his house. It was the beginning of the modern computer. Babbage failed to continue his research work in 1828 mainly because   _  .
A. he was in poor health
B. he almost ran out of money
C. his co-workers argued with him
D. he spent all his money on his bills
Answer: