What is the angle between the hour hand and the minute hand at seven o\textquotesingle clock?． 
Overseas Competition->Knowledge Point->Counting Modules->Permutations and Combinations->Combinations
The smaller angle is $\frac 5{12}$ of a full circle.  A full circle has $360$ degrees, so the angle is $\frac 5{12}\times 360^{}\circ =150^{}\circ $.  So, the answer is $\rm D$. 