Which of the following fractions is classified as a proper fraction?

A proper fraction is defined as a fraction where the numerator (the top number) is less than the denominator (the bottom number). In this case, the fraction 2/5 meets this criterion because 2 is indeed less than 5. Therefore, it is classified as a proper fraction.

The other options do not fit the definition of a proper fraction. For instance, 5/3 has a numerator greater than its denominator, making it an improper fraction. The same applies to 8/6, where the numerator exceeds the denominator, categorizing it as improper as well. The fraction 7/7 is equal to 1, which is typically considered a whole number rather than a fraction, and not classified as proper.