The correct answer is B. An act of falsely believing
Explanation:
In language, the meaning of an unknown word can be determined by using context clues, in which the words that surround the unknown word are used to determine the type of word and possible meaning of it or by using the prefixes or suffixes that are part of the word to infer the meaning of the unknown word. In this case in the sentence " One ancient misconception was that the Earth was flat" the unknown word or word to be studied is "misconception". Considering this word is used to describe the belief that Earth was flat and this is a false belief, it can be guessed through the context clues this word means a false belief or the act of believing something false. Similarly, if the prefix "miss" which means "mistaken" or "incorrect" is considered along with the word "conception" that means "to understand" it can be concluded a misconception is an incorrect or mistaken belief. Therefore, the word misconception means "an act of falsely believing".
