Read the article and select the best answer. Article: Parents are often amazed at how fast their child grows and develops. New research has determined that the ability to quantify may develop much sooner than most parents realize. Kristy vanMarle, professor of the University of Missouri, has determined that contrary to what previous studies have shown, infants are able to quantify substances --like sand or water--as early as 10 months. As long as the difference between the two substances is large enough, infants will choose the larger amount, especially when it comes to food. With the assistance of her team researchers, vanMarle tested the quantifying skills of babies by presenting them with two cups: one containing a small amount of food, and one containing a larger amount. Consistently, the babies chose the larger amount. "Several studies throughout the last 15 years have shown that infants are very good at telling how many objects they see; however, infants don't seem to count things like water or sand," vanMarle said. "What we're saying is that they can quantify substances; The infants can see how much food goes into each cup and compare that in their memories. They decide which amount is larger, and they almost always select the larger one." This information further refutes the long-held idea that babies "know nothing of the world," vanMarle said. "Since psychologists have begun studying infants with sensitive measures, we've discovered a lot of early abilities. I think for parents, it should be exciting to know that there's somebody there that has some fundamental and basic knowledge of the world, and that knowledge is guiding their development," vanMarle said. In the future, vanMarle says this kind of study could be linked to a child's progress in math-related skills, although programs marketed to increase those abilities, such as "Baby Einstein," still have mixed reviews when it comes to academic study. Question: Babies choose the larger amount of food _ . Options: A: by saying numbers B: with the help of parents C: on personal preference D: through their natural abilities
The answer to this question is:
D