Having Students Study Worked Examples in Order to Learn How

Having students study worked examples in order to learn how to solve problems

A) may be of benefit, but typically students are already aware of obvious solution strategies before they study these examples.
B) is actually detrimental to learning because it tricks students into thinking that they understand a particular problem when they really don't.
C) is probably a waste of time in the long run because it discourages independent inquiry and problem finding.
D) may be an effective strategy because it helps students form general problem-solving schemata.