Read the following paragraph:

One of the most popular dishes that people eat in Honduras is beans and rice. Each day, many Hondurans eat beans and rice for breakfast, lunch, and dinner, because they do not have the money to purchase other foods. Often, they start cooking a large pot of beans early in the morning and let them cook all day because the beans get soft and tender. Then, Hondurans can eat the beans whole or mash them into what we call refried beans. They add different vegetables and spices to the beans and rice to vary the taste of the food so the people will not get too tired of eating the same thing every day.

Which sentence contains an error using a linking word?

a. Each day, many Hondurans eat beans and rice for breakfast, lunch, and dinner because they do not have the money to purchase other foods.
b. Often, they cook a large pot of beans early in the morning and let them cook all day, because the beans get soft and tender.
c. They add different vegetables and spices to the beans and rice to vary the taste of the food so the people will not get too tired of eating the same thing every day.