Is the pooled sampling method of 250 students from three high schools a simple random sample?

The pooled sampling method described involves selecting 250 students from three high schools, and the correct answer indicates that this pool represents any group of students from the district. For a sample to be considered a simple random sample, each member of the population must have an equal chance of being selected, and there should be no bias in the selection process. If the students chosen truly could represent any 250 students from the entire district without favoritism toward any specific group or school, then it can be considered a simple random sample.

However, it is crucial to note that an effective simple random sample should also ensure that all students have an equal chance of being included, which is not explicitly confirmed in the answer choice. It's important to consider whether the methodology involved in selecting these students maintained that essential equal representation without bias towards particular schools or grades. If there was any systematic way of selecting these students that favored certain groups, then the designation of a simple random sample would be questionable.

Thus, while the answer provided highlights a key aspect that could qualify this sampling as random, further clarification on the selection process would be necessary to firmly support its status as a simple random sample.