Answer:
A small sample and a large standard deviation
Step-by-step explanation:
In statistics, the standard error is referred to as a phenomenon that generally measures or analyzes the accuracy thorough which a specific sample distribution signifies a particular population by utilizing "standard deviation". However, a sample mean tends to deviate from the 'real mean' of a given population and therefore the mentioned deviation represents the "standard error" of the mean.
According to the question, a small sample and a large standard deviation would produce the largest value to the standard error.