The answer is: <u>C. Error involving numbers. </u>
Explanation:
As a rule, numbers from one to ten must be spelled, as they are considered "small numbers", the rest can be written as "numerals" (11, 13, 120, etc..) There are no capitalization errors, as there are no proper nouns or after periods words, abbreviation errors are not involved in this sentence here, as there isn't any word abbreviated or that should be. No spelling erros, everything is perfectly spelled. And well, letter E, there is the erros; letter C.
