Which traversal method for a binary tree does the following Pascal code illustrate ( ) Procedure traverse(p:pointer) Begin If p＜＞nilthen begin traverse(p↑.left); process(p); traverse(p↑.right); endend;

A．preorder

B．postorder

C．reorder

D．inorder

要求风电机单机接地网的接地电阻≤（）Ω。但是对于山区等土壤电阻率较高的，接地电阻≤（）Ω。