Fehling’s test is positive for compounds with an aldehyde group (except for aromatic aldehydes) or alpha-hydroxy ketones.
The compounds that give a positive Fehling’s test are:
Other compounds, such as benzaldehyde, acetophenone, and 4-nitrobenzaldehyde, do not give a positive Fehling’s test because they are aromatic aldehydes or ketones.
Thus, the correct count is:
So, the correct answer is: 3